Statin as a Risk Factor for Cataract in Cases of Antioxidant Gene Polymorphism in Pakistani Population

Introduction: Cataract is main cause of reversible blindness and visual impairment. Risk factors include anti-hyperlipidemic drugs such as statin. However, the mechanism of statins as a risk factor for cataracts is not clear. The antioxidant effect of statin is reported in some studies while other studies showed negative results. This study was conducted to understand the association of cataract in statin users with antioxidant gene abnormalities. Objective: To investigate the risk factor of statin in the formation of cataracts in the Pakistani population. Methods: This was a multi-centric case-control study in Karachi, Pakistan between September 2019 and 2020. A single nucleotide polymorphism (SNP) at rs2070424 locus for superoxide dismutase (SOD1) gene, at rs1050450  for glutathione peroxidase (GPX) and rs7943316 locus for catalase (CAT), were examined with polymerase chain reaction (PCR) using high resolution melting curve (HRM) technique in 250 cataract patients. Results: The risk ratio with statin was seen and found that it was 1.5 times increased in SOD1 gene mutations, the statin benefit was 1.2 times reduced in GPX gene mutation and ratio was 1.1 in the CAT gene mutations. Conclusion: Statin is a risk factor for cataracts in those patients who have mutated antioxidant genes. The risk ratio of cataracts was found to be increased in the mutated genes of patients compared with non-mutated ones. This study proved the effect of statin as a risk factor associated with antioxidant genes in the development of cataracts in the Pakistani population.

Glucagon-like peptide 1 and its association with dipeptidyl peptidase IV in subjects with various degrees of glucose tolerance

Dipeptidyl peptidase IV (DPP-4) and Glucagon like peptide 1 (GLP-1) has profound effect on insulin and glucagon secretion; ultimately decreasing glucose levels. We find out the association of GLP-1 levels and DPP-4 in normal, impaired and newly diagnose type 2 diabetic glucose tolerance. Prospective case control study was conducted at Department of Physiology, Baqai Medical University by the collaboration of Baqai Institute of Diabetology and Endocrinology; Karachi-Pakistan. Study groups were categorized into three groups Control, Impaired glucose tolerant (IGT) and newly diagnose type 2 diabetes mellitus (NDD). Biochemical parameters were estimated by international standard protocols. Logistic regression analysis and Chi square test with statistical significance at p value <0.05 were applied. DPP-4 concentrations were significantly lower in NDD participants compared to control and IGT participants (p=0.01), whereas GLP-1 levels were significantly higher in Control than Impaired glucose tolerant and NDD (p = 0.013). GLP1 levels and SBP were also found to be positively correlated with serum DPP4 levels in NDD group (p<0.05). GLP1 and DPP4 levels in NDD group (p<0.05) and in controls (p<0.001) respectively showed strong significant positive correlation. Effective correlation between GLP1 and DPP4 was found as both contribute to control hyperglycemia in NDD and impaired glucose tolerant people.

Effects of season (summer & winter) on electrical characteristics of skeletal muscle membranes of the spiny-tailed lizard, Uromastix hardwickii

This study deals with the observation of changes with temperature variations of the seasons in the muscular electrical excitability in the reptile Uromastix hardwickii. Freshly captured adult animals of both the sexes were used in all the experiments, and the gastrocnemius (skeletal) muscles were dissected out. The muscle samples were digested with digestive fluid (pepsin & Hcl), stirred, settled and supernatant was removed, till whitish fluid having clear cells obtained for patch clamp recording of ionic currents and potentials. Resting membrane potentials and action potentials of reptilian cell membranes were measured in whole cell current mode. The glass microelectrodes, with a tip diameter 2-3 microm and tip resistance 5-6 MW (when filled with intracellular solution) were used in these experiments. The present study was carried out to investigate the electrical characteristics of the skeletal muscles of this species of Uromastix, which are not studied earlier. The average mean values of resting membrane potential, action potential and its durations showed no significant changes with the change in the season, but other components of action potential including threshold potential, after-potential and its duration were found to be increased significantly (P < 0.05) in summer as compared to winter. Temperature dependency of these parameters with seasonal variation, are studied for the first time in the gastrocnemius (skeletal) muscles of Uromastix hardwickii. Hence seasonal changes in the components of action potential are invariably associated with changes in environmental temperature, and may be responsible for changes in the activities and homeostasis of these animals; and possibly indicating underlying mechanism of hibernation.

Serum lipoprotein (a) in offspring of patients with premature myocardial infarction

OBJECTIVES

To compare serum Lp(a), lipids: TC, TG and lipoproteins: HDL-C and LDL-C levels of offspring with history of paternal myocardial infarction with the serum levels in offspring without paternal history of myocardial infarction.

SETTING

Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi.

METHODS

Thirty offspring between the ages of 8-25 years with the history of paternal myocardial infarction were randomly selected from population and were matched with offspring having no history of parental myocardial infarction.

RESULTS

Offspring of fathers who had a myocardial infarction tended to have a significantly raised level of Lp(a) (p < 0.001) compared with those without parental history. None of the other lipoprotein variables we examined exhibited a significant difference between the two groups of subjects.

CONCLUSION

The offspring of fathers with early myocardial infarction have higher mean values of Lp(a) than control subjects suggesting that this lipid variable may strongly predispose to CAD.