1.Lack of association of transthyretin variations with spinocerebellar ataxia in north Indian population
Mohammed Faruq ; Meenakshi Verma ; Harpreet ; Achal Kumar Srivastava ; Ritushree Kukreti ; Arijit Mukhopadhyay ; Nirmal Kumar Ganguly ; Vibha Taneja
Neurology Asia 2014;19(4):367-374
Background & Objective: Transthyretin (TTR) has been associated with spinocerebellar ataxia (SCA)
by several independent case reports. Coexistence of TTR and SCA mutations, overlapping clinical
symptoms as well as altered levels of TTR in SCA patients suggest a correlation between TTR and
SCA. To our knowledge, no large cohort based study has been attempted to examine the association of
SCA with polymorphism in TTR gene. Here, we chose to investigate TTR variations in SCA patients
(n=266) and controls (n=192) of North Indian ethnicity. Methods: We sequenced the exons including
exon-intron boundaries of TTR gene in 55 patients and 55 controls. We observed four variations
which were further genotyped by single base extension method (SNaPshot) in a larger cohort (SCA
patients n=211 and controls n=137). Results: A novel synonymous variation c.372 C>G in exon 4
was detected in heterozygous condition in one control sample. We found nominal association for
rs1800458 (Gly6Ser), with SCA (p-value < 0.05) which did not remain after Bonferroni correction
for multiple tests. Pairwise linkage disequilibrium (LD) analysis revealed no LD between studied
SNPs. Further, we employed two-marker sliding window analysis and observed a weak association of
haplotype AT of rs1800458 and rs1667251 with SCA patients (p-value <0.05) which was not retained
after Bonferroni correction.
Conclusion: Our data suggests no association of genetic variations of TTR in SCA pathology.
2.Contributing Factors to Diabetic Brain Injury and Cognitive Decline
Diabetes & Metabolism Journal 2019;43(5):560-567
The link of diabetes with co-occurring disorders in the brain involves complex and multifactorial pathways. Genetically engineered rodents that express familial Alzheimer's disease-associated mutant forms of amyloid precursor protein and presenilin 1 (PSEN1) genes provided invaluable insights into the mechanisms and consequences of amyloid deposition in the brain. Adding diabetes factors (obesity, insulin impairment) to these animal models to predict success in translation to clinic have proven useful at some extent only. Here, we focus on contributing factors to diabetic brain injury with the aim of identifying appropriate animal models that can be used to mechanistically dissect the pathophysiology of diabetes-associated cognitive dysfunction and how diabetes medications may influence the development and progression of cognitive decline in humans with diabetes.
Amyloid
;
Brain Injuries
;
Brain
;
Dementia
;
Diabetes Mellitus
;
Humans
;
Insulin
;
Models, Animal
;
Obesity
;
Plaque, Amyloid
;
Presenilin-1
;
Rodentia
3.Animals models of spinal cord contusion injury
Renuka VERMA ; Jasleen Kaur VIRDI ; Nirmal SINGH ; Amteshwar Singh JAGGI
The Korean Journal of Pain 2019;32(1):12-21
Spinal cord contusion injury is one of the most serious nervous system disorders, characterized by high morbidity and disability. To mimic spinal cord contusion in humans, various animal models of spinal contusion injury have been developed. These models have been developed in rats, mice, and monkeys. However, most of these models are developed using rats. Two types of animal models, i.e. bilateral contusion injury and unilateral contusion injury models, are developed using either a weight drop method or impactor method. In the weight drop method, a specific weight or a rod, having a specific weight and diameter, is dropped from a specific height on to the exposed spinal cord. Low intensity injury is produced by dropping a 5 g weight from a height of 8 cm, moderate injury by dropping 10 g weight from a height of 12.5–25 mm, and high intensity injury by dropping a 25 g weight from a height of 50 mm. In the impactor method, injury is produced through an impactor by delivering a specific force to the exposed spinal cord area. Mild injury is produced by delivering 100 ± 5 kdyn of force, moderate injury by delivering 200 ± 10 kdyn of force, and severe injury by delivering 300 ± 10 kdyn of force. The contusion injury produces a significant development of locomotor dysfunction, which is generally evident from the 0–14(th) day of surgery and is at its peak after the 28–56th day. The present review discusses different animal models of spinal contusion injury.
Animals
;
Body Weight
;
Cervical Vertebrae
;
Contusions
;
Female
;
Haplorhini
;
Humans
;
Locomotion
;
Methods
;
Mice
;
Models, Animal
;
Nervous System Diseases
;
Rats
;
Spinal Cord Injuries
;
Spinal Cord
4.Implications of oxidative stress in chronic kidney disease: a review on current concepts and therapies
Sagar VERMA ; Priyanka SINGH ; Shiffali KHURANA ; Nirmal Kumar GANGULY ; Ritushree KUKRETI ; Luciano SASO ; Devinder Singh RANA ; Vibha TANEJA ; Vinant BHARGAVA
Kidney Research and Clinical Practice 2021;40(2):183-193
Moderate levels of endogenous reactive oxygen species (ROS) are important for various cellular activities, but high levels lead to toxicity and are associated with various diseases. Levels of ROS are maintained as a balance between oxidants and antioxidants. Accumulating data suggest that oxidative stress is a major factor in deterioration of renal function. In this review, we highlight the possible mechanism by which oxidative stress can lead to chronic kidney disease (CKD). This review also describes therapies that counter the effect of oxidative stress in CKD patients. Numerous factors such as upregulation of genes involved in oxidative phosphorylation and ROS generation, chronic inflammation, vitamin D deficiency, and a compromised antioxidant defense mechanism system cause progressive detrimental effects on renal function that eventually lead to loss of kidney function. Patients with renal dysfunction are highly susceptible to oxidative stress, as risk factors such as diabetes, renal hypertension, dietary restrictions, hemodialysis, and old age predispose them to increased levels of ROS. Biomolecular adducts (DNA, proteins, and lipids) formed due to reaction with ROS can be used to determine oxidative stress levels. Based on the strong correlation between oxidative stress and CKD, reversal of oxidative stress is being explored as a major therapeutic option. Xanthine oxidase inhibitors, dietary antioxidants, and other agents that scavenge free radicals are gaining interest as treatment modalities in CKD patients.
5.Implications of oxidative stress in chronic kidney disease: a review on current concepts and therapies
Sagar VERMA ; Priyanka SINGH ; Shiffali KHURANA ; Nirmal Kumar GANGULY ; Ritushree KUKRETI ; Luciano SASO ; Devinder Singh RANA ; Vibha TANEJA ; Vinant BHARGAVA
Kidney Research and Clinical Practice 2021;40(2):183-193
Moderate levels of endogenous reactive oxygen species (ROS) are important for various cellular activities, but high levels lead to toxicity and are associated with various diseases. Levels of ROS are maintained as a balance between oxidants and antioxidants. Accumulating data suggest that oxidative stress is a major factor in deterioration of renal function. In this review, we highlight the possible mechanism by which oxidative stress can lead to chronic kidney disease (CKD). This review also describes therapies that counter the effect of oxidative stress in CKD patients. Numerous factors such as upregulation of genes involved in oxidative phosphorylation and ROS generation, chronic inflammation, vitamin D deficiency, and a compromised antioxidant defense mechanism system cause progressive detrimental effects on renal function that eventually lead to loss of kidney function. Patients with renal dysfunction are highly susceptible to oxidative stress, as risk factors such as diabetes, renal hypertension, dietary restrictions, hemodialysis, and old age predispose them to increased levels of ROS. Biomolecular adducts (DNA, proteins, and lipids) formed due to reaction with ROS can be used to determine oxidative stress levels. Based on the strong correlation between oxidative stress and CKD, reversal of oxidative stress is being explored as a major therapeutic option. Xanthine oxidase inhibitors, dietary antioxidants, and other agents that scavenge free radicals are gaining interest as treatment modalities in CKD patients.