To study impact of treatment with Rosuvastatin versus Atorvastatin on 25 hydroxy Vitamin D concentrations among adult Indian men- a randomized control trial

BACKGROUND

Dyslipidemias are on the rise and are increasingly being treated with statins. As the metabolism of cholecalciferol and cholesterol are interrelated, reduction in cholesterol synthesis by statins is likely to affect Vitamin D status.

OBJECTIVES

(1) The aim is to study the effect of treatment with statins (Atorvastatin/Rosuvastatin) on 25-hydroxy-Vitamin-D (25OHD) among newly detected subjects with dyslipidemia for 6 months (2) To study the impact of 25OHD concentrations on the efficacy of statin treatment.

MATERIALS AND METHODS

This was a prospective, balanced randomized (1:1), open-label, parallel-group study, in apparently healthy Indian adult men (south Asian, 40-60 years). At baseline, serum lipids and 25OHD concentrations were measured. Based on the Adult Treatment Panel III guidelines, subjects were divided as per lipid concentrations into controls (who did not require statin treatment) and intervention (who required statin treatment) groups. Random allocation of subjects was done in two groups for receiving intervention for 6 months: Atorvastatin group (n = 52, received Atorvastatin) or Rosuvastatin group (n = 52, received Rosuvastatin). Lipids and 25OHD concentrations were measured at the end line.

RESULTS

Atorvastatin group presented significant reduction (P < 0.05) in 25OHD, total cholesterol (TC) and low-density-lipoprotein-cholesterol (LDL-C) concentrations at the end line. In the Rosuvastatin group, significant drop in TC, LDL-C and high-density lipoprotein cholesterol (concentrations (P < 0.05) was observed, while 25OHD concentrations showed no significant change. Mean 25OHD concentrations were significantly correlated with a reduction in LDL-C concentrations in Atorvastatin group.

CONCLUSIONS

Treatment with Atorvastatin resulted in a reduction in 25OHD concentrations; further, its efficacy in reducing LDL-C concentrations was related to the 25OHD concentrations.

Paradoxical Response of Parathyroid Hormone to Vitamin D-Calcium Supplementation in Indian Children

OBJECTIVES

To investigate the effect of oral vitamin D-calcium supplementation on serum intact parathyroid hormone (PTH), calcium, phosphorous, and alkaline phosphatase (ALK-P) concentrations in children with habitually low calcium intakes.

STUDY DESIGN

In this follow-up study to a randomized controlled trial that aimed to assess the effect of vitamin D-calcium supplementation on immunity, data related to dietary intake, anthropometry, and biochemistry [serum 25(OH)D and bone profile] were collected from 178 children-79 in the vitamin D group and 99 in the non-vitamin D group.

RESULTS

Dietary calcium to phosphorus intake ratio was 0.4:1. Baseline serum 25(OH)D concentration was 58.2 ± 10.9 nmol/L; 66% children were vitamin D sufficient and none deficient. After supplementation, vitamin D group, compared with the non-vitamin D group, had significantly (P < .05) greater 25(OH)D (83.9 ± 30.1 nmol/L vs 58.3 ± 15.7 nmol/L), significantly greater PTH (6.7 ± 3.6 pmol/L vs 5.5 ± 3.2 pmol/L), and positive correlation (r_s = 0.24) between serum 25(OH)D and PTH (vs negative correlation [r_s = -0.1] in non-vitamin D group). Mean concentrations of serum bone measures in the vitamin D group were calcium (2.2 ± 0.1 mmol/L), phosphorus (1.7 ± 0.2 mmol/L), and ALK-P (178.7 ± 40.7 IU/L). At follow-up, 1-year post-supplementation, in the vitamin D group, PTH concentrations continued to remain high (but not significantly different from levels at 6 months), with low normal serum calcium, high normal phosphate, and ALK-P in reference range.

CONCLUSIONS

In children who are vitamin D sufficient but with habitually low dietary calcium intake, vitamin D-calcium supplementation paradoxically and significantly increased serum PTH concentrations with no apparent effect on other bone biochemistry. Chronic low dietary calcium to phosphorus ratio is likely to have caused this paradoxical response.

Duration of Casual Sunlight Exposure Necessary for Adequate Vitamin D Status in Indian Men

OBJECTIVES

To investigate the duration of casual sunlight ultraviolet-B (UVB) exposure required to maintain optimal Vitamin D status (25-hydroxyvitamin-D [25(OH)D]) >50 nmol/L in urban Indian men, using polysulfone (PSU) dosimeters and a sunlight exposure questionnaire.

METHODS

In healthy men (aged 40-60 years) from Pune (18.52° N, 73.86° E), India, serum 25(OH)D was measured using enzyme-linked immunosorbent assay. Sunlight exposure was assessed using PSU dosimeter and by questionnaire.

RESULTS

Of 160 men (48.3 ± 5.6 years), 26.8% were deficient and 40.6% had insufficient Vitamin D concentrations. A hyperbolic function for the relationship between PSU measured sunlight exposure in standard erythema dose (SED) and serum 25(OH)D concentrations (r = 0.87, P < 0.01) revealed that daily exposure of 1 SED was sufficient to maintain serum 25(OH)D concentrations over 50 nmol/L. The curve plateaued around 5 SED (80 nmol/L) and extrapolation of the curve (>5 SED) did not increase 25(OH)D concentrations above 90 nmol/L. Receiver operating curve analysis confirmed that 1 SED-UV exposure was sufficient to maintain 25(OH)D concentrations over 50 nmol/L. Based on the questionnaire data, >1 h of midday casual sunlight exposure was required to maintain serum 25(OH)D concentrations above 50 nmol/L. Duration of sunlight exposure assessed by questionnaire and PSU dosimeter showed a significant correlation (r = 0.517, P < 0.01).

CONCLUSION

In urban Indian men, >1 h of casual midday sunlight exposure daily was required to maintain serum 25(OH)D concentrations above 50 nmol/L, and >2 h of casual sunlight exposure was needed to maintain 25(OH)D concentrations above 75 nmol/L. Excess sunlight did not increase 25(OH)D linearly. The sunlight exposure questionnaire was validated for use in clinical studies and surveys.

Randomized Control Trial Assessing Impact of Increased Sunlight Exposure versus Vitamin D Supplementation on Lipid Profile in Indian Vitamin D Deficient Men

BACKGROUND

Despite abundance of sunshine in India, Vitamin D deficiency is common and therefore there is an increasing trend toward taking Vitamin D supplements either as prescription medicine or as a nutritional supplement. Studies have suggested that duration of sun exposure may influence serum lipid profile.

OBJECTIVES

To study the effect of increased sunlight exposure versus Vitamin D supplementation on Vitamin D status and lipid profile in individuals with Vitamin D deficiency (25-hydroxyvitamin-D [25OHD] <50 nmol/L).

DESIGN

A prospective, randomized open-label trial was carried out in apparently healthy Indian men (40-60 years). Based on 25OHD concentrations, individuals were divided into control (>50 nmol/L, n = 50) and intervention (<50 nmol/L, n = 100) groups. Individuals from intervention group were randomly allocated to two groups; either "increased sunlight exposure group" (n = 50, received at least 20 min sunlight exposure to forearms and face between 11 a.m. and 3 p.m. over and above their current exposure) or "cholecalciferol supplement group" (n = 50, received oral cholecalciferol 1000 IU/day).

RESULTS

Significant increase in 25OHD concentrations was seen in both intervention groups (P < 0.01). Significant decrease in total cholesterol (TC), high-density-lipoprotein cholesterol (HDL-C), and low-density-lipoprotein cholesterol (LDL-C) was seen in individuals with increased sunlight exposure (P < 0.05). Cholecalciferol supplement group showed a significant increase in TC and HDL-C (P < 0.05) and insignificant increase in LDL-C.

CONCLUSIONS

Increase in Vitamin D concentrations through sunlight exposure significantly reduced TC, LDL-C, and HDL-C concentrations, and cholecalciferol supplementation increased TC and HDL-C concentrations.

Relationship of insulin-like growth factor 1 and bone parameters in 7-15 years old apparently, healthy Indian children

OBJECTIVE

Growth hormone through insulin-like growth factor 1 (IGF-1) plays an important role in both bone growth and mineralization. This cross-sectional study was carried out to evaluate the relationship between serum IGF-1 concentrations and dual energy X-ray (DXA) measured whole body less head bone area (BA), lean body mass (LBM), and bone mineral content (BMC).

METHODS

One hundred and nineteen children (boys = 70, age = 7.3-15.6 years) were studied for their anthropometric parameters by standard methods and bone and body composition by DXA. Their fasting serum IGF-1 concentrations were assessed by enzyme-linked immunosorbent assay and Z-scores were calculated using available reference data. Bone and body composition parameter Z-scores were calculated using ethnic reference data.

RESULTS

Mean age of the boys and girls was similar (11.5 ± 1.8 years). The mean serum IGF-1concentrations and IGF-1 Z-scores were similar (P > 0.1) between boys and girls and were of the order of (302.3 ± 140.0 and - 1.4 ± 1.1, respectively). The LBM for age and BA for age Z-score was greater in children with IGF-1 Z-score > median than children with IGF-1 Z-score < median. The mean BMC for age Z-scores were 0.4 ± 0.9 and - 0.2 ± 0.8 in children with above and below the median of IGF-1 Z-score (P > 0.1).

CONCLUSION

Serum IGF-1 levels were more strongly associated with BA and LBM, suggesting that its effect on bone is greater with respect to periosteal bone acquisition and through its effect on muscle mass.

Lens protein phylogeny: immunocrossreactivity of vertebrate lens antigens to anti-shark crystallin antibody

Antisera prepared against total water-soluble lens proteins of the shark, Scoliodon sorrakowah were reacted with homologous antigen and analysed reaction products by immunoelectrophoresis (IE) and two dimensional crossed antigen-antibody electrophoresis (2D-CE). On IE, shark antigens formed 5 precipitin lines including 1 alpha, 3 beta and 1 gamma crystallins and on 2D-CE 3 alpha, 6 beta and 6 gamma peaks accounting for 8%, 27% and 65% antigen in the respective group were obtained from the total crystallins. Using anti-shark antisera, the immunocrossreactivity of lens proteins from 6 Chondropterygii, 23 teleosts and 16 higher vertebrates was examined by IE. It is found that beta crystallins are the most conserved and crossreact with all vertebrate classes, whereas gamma crystallin crossreactivity is specific to the class Pisces and alpha crystallins are least conserved and their crossreactivity is confined to subclass Chondropterygii. Based on IE patterns, a phylogenetic tree is constructed which demonstrates the intrafamily closeness except in case of adaptive radiation.