1,721,101 research outputs found
Role of the sympathetic nervous system in the development of hypertension and metabolic syndrome in low birth weight offspring
No full textThe sympathetic nervous system plays a pivotal role in the development of the metabolic syndrome particularly hypertension in low birth weight offspring. The Barker hypothesis reported that individuals born with low birth weight were at risk of developing chronic diseases later in life. Animal and human studies have since confirmed this relationship, however the mechanisms involved remain unknown. Therefore, this study investigated the role of the sympathetic nervous system in protein restricted rats and pre-clinical University of Zimbabwe students whose birth weights were less than 2.5kg. According to the Barker hypothesis adverse influences early in foetal development can result in permanent changes in the metabolism and physiology with such changes resulting in increased disease risk of the metabolic syndrome in adulthood. It was hypothesized that the sympathetic nervous system was the mechanism by which themetabolic syndrome particularly hypertension occurred in low birth weight and intrauterine growth restricted offspring.
An intrauterine growth restricted (IUGR) rat model was developed using local Zimbabweans diets. Using this model, mean blood pressure (mmHg) measured using the tail cuff method was significantly higher within 10 weeks in IUGR rats than in normal rats (122.46±2.73 vs 106.50±5.81 p=0.0001). The blood pressure significantly decreased in IUGR rats whose renal nerve (sympathetic influence) had been denervated (103.44±8.17mmHg vs 98.49±7.85mmHg p=0.013).
A series of human experiments were then conducted in young adults from the University of Zimbabwe. The students were put through exercise paces to allow the expression of the autonomic nervous system. Heart Rate Variability (HRV) ratio, and Pulse Wave Amplitude (PWA) responses to activation of the muscle metaboreflex were exaggerated in low birth weight (LBW) compared to normal birth weight (NBW) offspring (HRV: 1.015±1.034 vs 0.119±0.789 p<0.05) PWA: -1.320±1.064 vs -0.735±0.63 mV p=0.28. This suggested that the exercise pressor reflex, which is involved in tight regulation of the cardiovascular response to exercise, is persistently dysregulated into early adulthood for LBW individuals.
The study showed a significant difference in decrease in diastolic function (E/A ratio) in LBW than NBW groups ( 0.48±0.27 vs 0.19±0.18 p=0.031) and a significant association between LBW and exercise induced cardiac fatigue with diastolic dysfunction (p<0.001 odds risk ratio 7.5[95% CI 2.7-20.7]). Furthermore, the mechanisms of exercise induced cardiac fatigue involved transient myocardial stunning and a decrease in sensitivity of myocardium to catecholamines reducing the effect of adrenaline in improving both systolic and diastolic function during exercise.
LBW was associated with exercise induced hypertension (EIH) (62% vs 32% p<0.05) and post exercise hypotension (PEH) in young adults, a phenomenon hypothesised to be mediated by two processes; physiological down regulation of the cholinergic sympathetic vasodilator receptors in peripheral tissues due to chronic sympathetic stimulation; and increased wall thickening (EIH) and derangements in sympathetic tone (PEH). In the glucose tolerance study in LBW young adults had elevated sympathetic activity and were glucose intolerant (after 60mins 8.4±.56 mmol/l vs 7.57±0.36mmol/l p=0.035).
It is concluded that the sympathetic nervous system possibly has a role in the development of the metabolic syndrome in low birth weight humans and intrauterine growth restricted rats.National Institute of Neurological Disorders and Stroke (NINDS).
Office of the Director -National Institutes of Health (OD) and National Heart,
Lung, And Blood Institute (NHLBI) through a Medical Education Partnership Initiative
(MEPI) Grant to the University of Zimbabwe College of Health Sciences and Southern
Africa Consortium for Research Excellence (SACORE) and the University of
Zimbabwe College of Health Sciences Physiology Department
Role of the sympathetic nervous system in the development of hypertension and metabolic syndrome in low birth weight offspring
No full textThe sympathetic nervous system plays a pivotal role in the development of the metabolic syndrome particularly hypertension in low birth weight offspring. The Barker hypothesis reported that individuals born with low birth weight were at risk of developing chronic diseases later in life. Animal and human studies have since confirmed this relationship, however the mechanisms involved remain unknown. Therefore, this study investigated the role of the sympathetic nervous system in protein restricted rats and pre-clinical University of Zimbabwe students whose birth weights were less than 2.5kg. According to the Barker hypothesis adverse influences early in foetal development can result in permanent changes in the metabolism and physiology with such changes resulting in increased disease risk of the metabolic syndrome in adulthood. It was hypothesized that the sympathetic nervous system was the mechanism by which themetabolic syndrome particularly hypertension occurred in low birth weight and intrauterine growth restricted offspring.
An intrauterine growth restricted (IUGR) rat model was developed using local Zimbabweans diets. Using this model, mean blood pressure (mmHg) measured using the tail cuff method was significantly higher within 10 weeks in IUGR rats than in normal rats (122.46±2.73 vs 106.50±5.81 p=0.0001). The blood pressure significantly decreased in IUGR rats whose renal nerve (sympathetic influence) had been denervated (103.44±8.17mmHg vs 98.49±7.85mmHg p=0.013).
A series of human experiments were then conducted in young adults from the University of Zimbabwe. The students were put through exercise paces to allow the expression of the autonomic nervous system. Heart Rate Variability (HRV) ratio, and Pulse Wave Amplitude (PWA) responses to activation of the muscle metaboreflex were exaggerated in low birth weight (LBW) compared to normal birth weight (NBW) offspring (HRV: 1.015±1.034 vs 0.119±0.789 p<0.05) PWA: -1.320±1.064 vs -0.735±0.63 mV p=0.28. This suggested that the exercise pressor reflex, which is involved in tight regulation of the cardiovascular response to exercise, is persistently dysregulated into early adulthood for LBW individuals.
The study showed a significant difference in decrease in diastolic function (E/A ratio) in LBW than NBW groups ( 0.48±0.27 vs 0.19±0.18 p=0.031) and a significant association between LBW and exercise induced cardiac fatigue with diastolic dysfunction (p<0.001 odds risk ratio 7.5[95% CI 2.7-20.7]). Furthermore, the mechanisms of exercise induced cardiac fatigue involved transient myocardial stunning and a decrease in sensitivity of myocardium to catecholamines reducing the effect of adrenaline in improving both systolic and diastolic function during exercise.
LBW was associated with exercise induced hypertension (EIH) (62% vs 32% p<0.05) and post exercise hypotension (PEH) in young adults, a phenomenon hypothesised to be mediated by two processes; physiological down regulation of the cholinergic sympathetic vasodilator receptors in peripheral tissues due to chronic sympathetic stimulation; and increased wall thickening (EIH) and derangements in sympathetic tone (PEH). In the glucose tolerance study in LBW young adults had elevated sympathetic activity and were glucose intolerant (after 60mins 8.4±.56 mmol/l vs 7.57±0.36mmol/l p=0.035).
It is concluded that the sympathetic nervous system possibly has a role in the development of the metabolic syndrome in low birth weight humans and intrauterine growth restricted rats.,National Institute of Neurological Disorders and Stroke (NINDS).
Office of the Director -National Institutes of Health (OD) and National Heart,
Lung, And Blood Institute (NHLBI) through a Medical Education Partnership Initiative
(MEPI) Grant to the University of Zimbabwe College of Health Sciences and Southern
Africa Consortium for Research Excellence (SACORE) and the University of
Zimbabwe College of Health Sciences Physiology Department
Development, safety and efficacy evaluation of actinic damage retarding nano-pharmaceutical treatments in oculocutaneous albinism
No full textIntroduction: There are at least 17 000 Persons living with albinism (PLWA) in Zimbabwe. Oculocutaneous albinism (OCA) is a congenital amelanistic pigmentation disorder that affects all known vertebrates and has no known cure. Melanogenesis is the body’s primary protection from actinic damage, which summarizes all the acute and chronic solar induced adverse dermatological conditions. This impairment therefore makes PLWA highly susceptible to all forms of this damage.
Problem statement: Commercial products for actinic damage in PLWA are not readily available. Chemical sunscreens used by PLWA are ineffective and do not treat symptoms of actinic damage. The possible use of promising broad spectrum physical sunscreens in albinistic treatments is hindered by their opaque and un-aesthetic nature.
Research hypothesis: A treatment based on nanometric TiO2 and ZnO incorporating the active extracts of A. excelsa, T. emetica and M. flabellifolia will be aesthetic, efficacious and safe in retarding and alleviating all forms of actinic damage in PLWA.
Research aims: To develop albinistic actinic damage treatments, using nano TiO2 and ZnO as sun-blocks and incorporating selected herbs. The dermato-pharmacokinetics, stability, efficacy, toxicity and aesthetics of the resultant formulation on albinistic skin types were also investigated in this study.
Materials and methods: Emulsion formulation was done according to FDA-CFSAN, COLIPA, and OECD mandated technical guidelines and testing methods. Formulation skin sensitivity were evaluated through Draize ocular and skin sensitivity tests as well as in-vivo patch tests guided by OECD 428/404 technical guidelines and opinion SCCNFP 0750/03. Percutaneous absorption and albinistic skin dermato-pharmacokinetics were evaluated ex-vivo using Franz diffusion tests and sequential adhesive tape stripping respectively according to OECD guidelines 428 and SCCNFP opinions as well as related work done by A O Gamer and Diembeck et al as guides. Analysis for Ti and Zn were done by ICP-AES and Flame AAS respectively. Efficacy and SPF testing was done as per FDA–CFSAN, Colipa and OECD M389/EN mandated test methods.
Principal Results: SPF 16, aesthetic and stable emulsions were formulated. Negligible irritation indices for the treatment were recorded for Draize and human patch testing. No percutaneous absorption was observed for ex-vivo diffusion tests and sequential tape stripping tests. Different skin reservoir properties were observed at different skin sites
Conclusions: The studies demonstrate, direct evidence that neither Zn nor Ti can penetrate actinic damaged skin regardless of anatomical site and that albinistic dermato-pharmacokinetics are depended on anatomical region and extent of UVR exposure. The high extraction yields and the phyto-constituents of the selected herbs show a correlation with the traditional uses of the plants in traditional medicine. All sensitivity tests showed negligible irritation potential. Based on the foregoing, it is concluded that, incorporation of nanometric TiO2, ZnO and herbs in treatments to retard actinic damage in PLWA is feasible, aesthetic, efficacious, and commercializable and does not pose any health risk.,Harare Institute of Technology.
University of Zimbabwe Research Grant.
ICF Grant from the Government of Zimbabwe
Development, safety and efficacy evaluation of actinic damage retarding nano-pharmaceutical treatments in oculocutaneous albinism
No full textIntroduction: There are at least 17 000 Persons living with albinism (PLWA) in Zimbabwe. Oculocutaneous albinism (OCA) is a congenital amelanistic pigmentation disorder that affects all known vertebrates and has no known cure. Melanogenesis is the body’s primary protection from actinic damage, which summarizes all the acute and chronic solar induced adverse dermatological conditions. This impairment therefore makes PLWA highly susceptible to all forms of this damage.
Problem statement: Commercial products for actinic damage in PLWA are not readily available. Chemical sunscreens used by PLWA are ineffective and do not treat symptoms of actinic damage. The possible use of promising broad spectrum physical sunscreens in albinistic treatments is hindered by their opaque and un-aesthetic nature.
Research hypothesis: A treatment based on nanometric TiO2 and ZnO incorporating the active extracts of A. excelsa, T. emetica and M. flabellifolia will be aesthetic, efficacious and safe in retarding and alleviating all forms of actinic damage in PLWA.
Research aims: To develop albinistic actinic damage treatments, using nano TiO2 and ZnO as sun-blocks and incorporating selected herbs. The dermato-pharmacokinetics, stability, efficacy, toxicity and aesthetics of the resultant formulation on albinistic skin types were also investigated in this study.
Materials and methods: Emulsion formulation was done according to FDA-CFSAN, COLIPA, and OECD mandated technical guidelines and testing methods. Formulation skin sensitivity were evaluated through Draize ocular and skin sensitivity tests as well as in-vivo patch tests guided by OECD 428/404 technical guidelines and opinion SCCNFP 0750/03. Percutaneous absorption and albinistic skin dermato-pharmacokinetics were evaluated ex-vivo using Franz diffusion tests and sequential adhesive tape stripping respectively according to OECD guidelines 428 and SCCNFP opinions as well as related work done by A O Gamer and Diembeck et al as guides. Analysis for Ti and Zn were done by ICP-AES and Flame AAS respectively. Efficacy and SPF testing was done as per FDA–CFSAN, Colipa and OECD M389/EN mandated test methods.
Principal Results: SPF 16, aesthetic and stable emulsions were formulated. Negligible irritation indices for the treatment were recorded for Draize and human patch testing. No percutaneous absorption was observed for ex-vivo diffusion tests and sequential tape stripping tests. Different skin reservoir properties were observed at different skin sites
Conclusions: The studies demonstrate, direct evidence that neither Zn nor Ti can penetrate actinic damaged skin regardless of anatomical site and that albinistic dermato-pharmacokinetics are depended on anatomical region and extent of UVR exposure. The high extraction yields and the phyto-constituents of the selected herbs show a correlation with the traditional uses of the plants in traditional medicine. All sensitivity tests showed negligible irritation potential. Based on the foregoing, it is concluded that, incorporation of nanometric TiO2, ZnO and herbs in treatments to retard actinic damage in PLWA is feasible, aesthetic, efficacious, and commercializable and does not pose any health risk.Harare Institute of Technology.
University of Zimbabwe Research Grant.
ICF Grant from the Government of Zimbabwe
Development, safety and efficacy evaluation of actinic damage retarding nano-pharmaceutical treatments in oculocutaneous albinism
No full textIntroduction: There are at least 17 000 Persons living with albinism (PLWA) in Zimbabwe. Oculocutaneous albinism (OCA) is a congenital amelanistic pigmentation disorder that affects all known vertebrates and has no known cure. Melanogenesis is the body’s primary protection from actinic damage, which summarizes all the acute and chronic solar induced adverse dermatological conditions. This impairment therefore makes PLWA highly susceptible to all forms of this damage.
Problem statement: Commercial products for actinic damage in PLWA are not readily available. Chemical sunscreens used by PLWA are ineffective and do not treat symptoms of actinic damage. The possible use of promising broad spectrum physical sunscreens in albinistic treatments is hindered by their opaque and un-aesthetic nature.
Research hypothesis: A treatment based on nanometric TiO2 and ZnO incorporating the active extracts of A. excelsa, T. emetica and M. flabellifolia will be aesthetic, efficacious and safe in retarding and alleviating all forms of actinic damage in PLWA.
Research aims: To develop albinistic actinic damage treatments, using nano TiO2 and ZnO as sun-blocks and incorporating selected herbs. The dermato-pharmacokinetics, stability, efficacy, toxicity and aesthetics of the resultant formulation on albinistic skin types were also investigated in this study.
Materials and methods: Emulsion formulation was done according to FDA-CFSAN, COLIPA, and OECD mandated technical guidelines and testing methods. Formulation skin sensitivity were evaluated through Draize ocular and skin sensitivity tests as well as in-vivo patch tests guided by OECD 428/404 technical guidelines and opinion SCCNFP 0750/03. Percutaneous absorption and albinistic skin dermato-pharmacokinetics were evaluated ex-vivo using Franz diffusion tests and sequential adhesive tape stripping respectively according to OECD guidelines 428 and SCCNFP opinions as well as related work done by A O Gamer and Diembeck et al as guides. Analysis for Ti and Zn were done by ICP-AES and Flame AAS respectively. Efficacy and SPF testing was done as per FDA–CFSAN, Colipa and OECD M389/EN mandated test methods.
Principal Results: SPF 16, aesthetic and stable emulsions were formulated. Negligible irritation indices for the treatment were recorded for Draize and human patch testing. No percutaneous absorption was observed for ex-vivo diffusion tests and sequential tape stripping tests. Different skin reservoir properties were observed at different skin sites
Conclusions: The studies demonstrate, direct evidence that neither Zn nor Ti can penetrate actinic damaged skin regardless of anatomical site and that albinistic dermato-pharmacokinetics are depended on anatomical region and extent of UVR exposure. The high extraction yields and the phyto-constituents of the selected herbs show a correlation with the traditional uses of the plants in traditional medicine. All sensitivity tests showed negligible irritation potential. Based on the foregoing, it is concluded that, incorporation of nanometric TiO2, ZnO and herbs in treatments to retard actinic damage in PLWA is feasible, aesthetic, efficacious, and commercializable and does not pose any health risk.Harare Institute of Technology.
University of Zimbabwe Research Grant.
ICF Grant from the Government of Zimbabwe
Role of the sympathetic nervous system in the development of hypertension and metabolic syndrome in low birth weight offspring
No full textThe sympathetic nervous system plays a pivotal role in the development of the metabolic syndrome particularly hypertension in low birth weight offspring. The Barker hypothesis reported that individuals born with low birth weight were at risk of developing chronic diseases later in life. Animal and human studies have since confirmed this relationship, however the mechanisms involved remain unknown. Therefore, this study investigated the role of the sympathetic nervous system in protein restricted rats and pre-clinical University of Zimbabwe students whose birth weights were less than 2.5kg. According to the Barker hypothesis adverse influences early in foetal development can result in permanent changes in the metabolism and physiology with such changes resulting in increased disease risk of the metabolic syndrome in adulthood. It was hypothesized that the sympathetic nervous system was the mechanism by which themetabolic syndrome particularly hypertension occurred in low birth weight and intrauterine growth restricted offspring.
An intrauterine growth restricted (IUGR) rat model was developed using local Zimbabweans diets. Using this model, mean blood pressure (mmHg) measured using the tail cuff method was significantly higher within 10 weeks in IUGR rats than in normal rats (122.46±2.73 vs 106.50±5.81 p=0.0001). The blood pressure significantly decreased in IUGR rats whose renal nerve (sympathetic influence) had been denervated (103.44±8.17mmHg vs 98.49±7.85mmHg p=0.013).
A series of human experiments were then conducted in young adults from the University of Zimbabwe. The students were put through exercise paces to allow the expression of the autonomic nervous system. Heart Rate Variability (HRV) ratio, and Pulse Wave Amplitude (PWA) responses to activation of the muscle metaboreflex were exaggerated in low birth weight (LBW) compared to normal birth weight (NBW) offspring (HRV: 1.015±1.034 vs 0.119±0.789 p<0.05) PWA: -1.320±1.064 vs -0.735±0.63 mV p=0.28. This suggested that the exercise pressor reflex, which is involved in tight regulation of the cardiovascular response to exercise, is persistently dysregulated into early adulthood for LBW individuals.
The study showed a significant difference in decrease in diastolic function (E/A ratio) in LBW than NBW groups ( 0.48±0.27 vs 0.19±0.18 p=0.031) and a significant association between LBW and exercise induced cardiac fatigue with diastolic dysfunction (p<0.001 odds risk ratio 7.5[95% CI 2.7-20.7]). Furthermore, the mechanisms of exercise induced cardiac fatigue involved transient myocardial stunning and a decrease in sensitivity of myocardium to catecholamines reducing the effect of adrenaline in improving both systolic and diastolic function during exercise.
LBW was associated with exercise induced hypertension (EIH) (62% vs 32% p<0.05) and post exercise hypotension (PEH) in young adults, a phenomenon hypothesised to be mediated by two processes; physiological down regulation of the cholinergic sympathetic vasodilator receptors in peripheral tissues due to chronic sympathetic stimulation; and increased wall thickening (EIH) and derangements in sympathetic tone (PEH). In the glucose tolerance study in LBW young adults had elevated sympathetic activity and were glucose intolerant (after 60mins 8.4±.56 mmol/l vs 7.57±0.36mmol/l p=0.035).
It is concluded that the sympathetic nervous system possibly has a role in the development of the metabolic syndrome in low birth weight humans and intrauterine growth restricted rats
Role of the Sympathetic Nervous System in the Development of Hypertension and Metabolic Syndrome in Low Birth Weight Offspring
No full textThe sympathetic nervous system plays a pivotal role in the development of the metabolic
syndrome particularly hypertension in low birth weight offspring. The Barker hypothesis
reported that individuals born with low birth weight were at risk of developing chronic diseases
later in life. Animal and human studies have since confirmed this relationship, however the
mechanisms involved remain unknown. Therefore, this study investigated the role of the
sympathetic nervous system in protein restricted rats and pre-clinical University of Zimbabwe
students whose birth weights were less than 2.5kg. According to the Barker hypothesis
adverse influences early in foetal development can result in permanent changes in the
metabolism and physiology with such changes resulting in increased disease risk of the
metabolic syndrome in adulthood. It was hypothesized that the sympathetic nervous system
was the mechanism by which the metabolic syndrome particularly hypertension occurred in
low birth weight and intrauterine growth restricted offspring.
An intrauterine growth restricted (IUGR) rat model was developed using local Zimbabweans
diets. Using this model, mean blood pressure (mmHg) measured using the tail cuff method
was significantly higher within 10 weeks in IUGR rats than in normal rats (122.46±2.73 vs
106.50±5.81 p=0.0001). The blood pressure significantly decreased in IUGR rats whose renal
nerve (sympathetic influence) had been denervated (103.44±8.17mmHg vs 98.49±7.85mmHg
p=0.013).
A series of human experiments were then conducted in young adults from the University of
Zimbabwe. The students were put through exercise paces to allow the expression of the
autonomic nervous system. Heart Rate Variability (HRV) ratio, and Pulse Wave Amplitude
(PWA) responses to activation of the muscle metaboreflex were exaggerated in low birth
weight (LBW) compared to normal birth weight (NBW) offspring (HRV: 1.015±1.034 vs
0.119±0.789 p<0.05) PWA: -1.320±1.064 vs -0.735±0.63 mV p=0.28. This suggested that the
exercise pressor reflex, which is involved in tight regulation of the cardiovascular response to
exercise, is persistently dysregulated into early adulthood for LBW individuals.
The study showed a significant difference in decrease in diastolic function (E/A ratio) in LBW
than NBW groups ( 0.48±0.27 vs 0.19±0.18 p=0.031) and a significant association between
LBW and exercise induced cardiac fatigue with diastolic dysfunction (p<0.001 odds risk ratio
7.5[95% CI 2.7-20.7]). Furthermore, the mechanisms of exercise induced cardiac fatigue
involved transient myocardial stunning and a decrease in sensitivity of myocardium to
catecholamines reducing the effect of adrenaline in improving both systolic and diastolic
function during exercise.
LBW was associated with exercise induced hypertension (EIH) (62% vs 32% p<0.05) and post
exercise hypotension (PEH) in young adults, a phenomenon hypothesised to be mediated by
two processes; physiological down regulation of the cholinergic sympathetic vasodilator
receptors in peripheral tissues due to chronic sympathetic stimulation; and increased wall
thickening (EIH) and derangements in sympathetic tone (PEH). In the glucose tolerance study
in LBW young adults had elevated sympathetic activity and were glucose intolerant (after
60mins 8.4±.56 mmol/l vs 7.57±0.36mmol/l p=0.035).
It is concluded that the sympathetic nervous system possibly has a role in the development of
the metabolic syndrome in low birth weight humans and intrauterine growth restricted rats
Development, safety and efficacy evaluation of actinic damage retarding nano-pharmaceutical treatments in oculocutaneous albinism
No full textIntroduction: There are at least 17 000 Persons living with albinism (PLWA) in Zimbabwe. Oculocutaneous albinism (OCA) is a congenital amelanistic pigmentation disorder that affects all known vertebrates and has no known cure. Melanogenesis is the body’s primary protection from actinic damage, which summarizes all the acute and chronic solar induced adverse dermatological conditions. This impairment therefore makes PLWA highly susceptible to all forms of this damage.
Problem statement: Commercial products for actinic damage in PLWA are not readily available. Chemical sunscreens used by PLWA are ineffective and do not treat symptoms of actinic damage. The possible use of promising broad spectrum physical sunscreens in albinistic treatments is hindered by their opaque and un-aesthetic nature.
Research hypothesis: A treatment based on nanometric TiO2 and ZnO incorporating the active extracts of A. excelsa, T. emetica and M. flabellifolia will be aesthetic, efficacious and safe in retarding and alleviating all forms of actinic damage in PLWA.
Research aims: To develop albinistic actinic damage treatments, using nano TiO2 and ZnO as sun-blocks and incorporating selected herbs. The dermato-pharmacokinetics, stability, efficacy, toxicity and aesthetics of the resultant formulation on albinistic skin types were also investigated in this study.
Materials and methods: Emulsion formulation was done according to FDA-CFSAN, COLIPA, and OECD mandated technical guidelines and testing methods. Formulation skin sensitivity were evaluated through Draize ocular and skin sensitivity tests as well as in-vivo patch tests guided by OECD 428/404 technical guidelines and opinion SCCNFP 0750/03. Percutaneous absorption and albinistic skin dermato-pharmacokinetics were evaluated ex-vivo using Franz diffusion tests and sequential adhesive tape stripping respectively according to OECD guidelines 428 and SCCNFP opinions as well as related work done by A O Gamer and Diembeck et al as guides. Analysis for Ti and Zn were done by ICP-AES and Flame AAS respectively. Efficacy and SPF testing was done as per FDA–CFSAN, Colipa and OECD M389/EN mandated test methods.
Principal Results: SPF 16, aesthetic and stable emulsions were formulated. Negligible irritation indices for the treatment were recorded for Draize and human patch testing. No percutaneous absorption was observed for ex-vivo diffusion tests and sequential tape stripping tests. Different skin reservoir properties were observed at different skin sites
Conclusions: The studies demonstrate, direct evidence that neither Zn nor Ti can penetrate actinic damaged skin regardless of anatomical site and that albinistic dermato-pharmacokinetics are depended on anatomical region and extent of UVR exposure. The high extraction yields and the phyto-constituents of the selected herbs show a correlation with the traditional uses of the plants in traditional medicine. All sensitivity tests showed negligible irritation potential. Based on the foregoing, it is concluded that, incorporation of nanometric TiO2, ZnO and herbs in treatments to retard actinic damage in PLWA is feasible, aesthetic, efficacious, and commercializable and does not pose any health risk
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