Protective role of cod liver oil on hippocampal oxidative damage and neuronal count in Wistar rat model of comorbid depression

Background

Proper nutrition and balanced diet have a profound influence on mental well-being. Nutritional psychiatry plays an important role in influencing a healthy mind and body. The animal model of chronic unpredictable stress has been considered the effective model to explore research on anxiety and depression.

Aim

The present study aimed to explore the protective role of cod liver oil on various biochemical and neuronal analyses in the hippocampus tissue of the Wistar rat model of comorbid depression.

Methods

Healthy adult albino rats of Wistar strain weighing (120-160 g) were divided into control groups and experimental groups. These groups were further categorized into various subgroups based on stress exposure, cod liver oil, and antidepressant treatment. Six animals were taken in each group. The duration of stress exposure was for 15 days. After the experimentation procedure, the animals were anesthetized and hippocampus was dissected for the estimations of various biochemical and neurological parameters.

Results

The combination of cod liver oil with the antidepressant significantly (p < 0.001) decreased the lipid peroxidation level. Total antioxidant (TAO) and superoxide dismutase (SOD) levels significantly increased (p < 0.001) in the hippocampus. Treatment of cod liver oil during the stress exposure increased (p < 0.001) the neuronal count.

Conclusion

Cod liver oil proved to be an effective antidepressant agent by increasing the antioxidants and promoting neurogenesis in the hippocampus.

Levetiracetam exposure during prenatal and postnatal period induces cognitive decline in rat offsprings, not completely prevented by Bacopa monnieri

OBJECTIVES

Levetiracetam (LEV) is an antiepileptic recommended during pregnancy. Bacopa monneri is a medicinal herb used in Ayurveda for improvement of cognition. Data on effects of LEV and Bacopa on cognition is inadequate. The study evaluated the cognitive effects of LEV on rat offspring of dams exposed to LEV and whether pretreatment with Bacopa monnieri, inhibits the potential cognitive decline by LEV.

METHODS

Pregnant rats were allocated into four groups of three rats each. Groups 1, 2, 3 and 4 received 2% gum acacia, LEV 270 mg/kg, LEV 270 mg/kg + Bacopa 100 mg/kg and LEV 270 mg/kg + Bacopa 200 mg/kg respectively during pregnancy and lactation. Three pups from all dams were chosen at random and exposed to passive avoidance, Hebb-Williams and Morris water maze tests to check for their cognition and relevant histopathology was done.

RESULTS

In the passive avoidance model groups 3 and 4, showed an increase in escape latency compared with group 2, demonstrating an improved learning (p=0.05). In Hebb-Williams maze, the time taken to reach reward chamber by group 2 increased compared to group 1, p=0.006, showing cognitive decline. Neuronal count in hippocampus and prefrontal cortex decreased significantly in group 2, which improved in group 3 & 4 however there was distortion of architecture in group 4.

CONCLUSIONS

LEV exposure in intrauterine and neonatal period induced cognitive decline in rat offsprings and Bacopa 100 mg/kg prevented LEV induced cognitive decline. However safety of exposure to Bacopa during the gestation period has to be evaluated.

Dimensions of pes anserinus of the lower extremity, an anatomical study with its surgical implications

The reconstructive surgeries utilize pes anserinus (PA) tendons, because of their lesser post-operative clinical deficits and donor site morbidity. These surgeries require anatomical knowledge about the extent of PA formation. The goal of this study was to determine the length and width of the PA formation. The objectives were to measure the distance of its upper limit, lower limit, and vertical distance from the tibial tuberosity (TT). The present descriptive cross sectional study included 53 embalmed cadaveric lower extremities. The upper and lower limits of PA were exposed with the careful dissection. Measurements of the dimensions were performed with the help of a digital vernier caliper (Mitutoyo Co., Kanagawa, Japan). The PA length, width, distance of its upper limit, lower limit, and vertical distance of it from the TT were 47.4±13.3 mm, 37.3±7.2 mm, 47.6±12.5 mm, 54.6±10.4 mm, and 39.1±14.2 mm, respectively over the right extremity. The same measurements were 46.3±14.7 mm, 39.1±9.4 mm, 39.1±5.9 mm, 49.5±8.2 mm, and 36.4±12.1 mm, respectively for the left extremity. The extent of PA was observed to be extremely variable. The preoperative knowledge about the dimensions of PA will help the plastic and orthopedic surgeon put the accurate skin incision, decreasing the donor site morbidity and biomechanical instability of the PA grafts. We suggest that, preoperative ultrasound measurement of the PA may help the operating surgeon to prevent the complications like injury to the infrapatellar branch of saphenous nerve.

Chronic unpredictable stress-induced inflammation and quantitative analysis of neurons of distinct brain regions in Wistar rat model of comorbid depression

Background and Aim:

Depression and anxiety are the most prominent neuropsychiatric disease and have been considered as the most burdensome diseases of society. The hippocampus and prefrontal cortex have a prominent role in stress-induced neurological disorders. Chronic unpredictable stress exposed rats are a perfect model in understanding comorbid depression and anxiety disorders. The inflammatory response occurring in the body has been linked to C-reactive protein (CRP) in many diseased conditions. The present research primarily focus on the possible correlation of Cortisol, CRP level and neuronal assay in different regions of hippocampus, dentate gyrus (DG), and prefrontal cortex.

Materials and Methods:

The control group of rats (n=6) was not exposed to any stress. Whereas, the experimental stress group (n=6) of rats was exposed to various stressors for 15 days. After the experimentation procedures, the blood samples were collected and brain dissection was done. The neurons in the prefrontal cortex, the DG along with various hippocampal regions was counted. Statistical analysis was performed using student’s t-test and p<0.05 was expressed as statistically significant.

Results:

Animals exposed to chronic unpredictable stressors showed a significant (p<0.0001) decrease in the neuronal count in prefrontal cortex and hippocampus. A significant rise in the serum cortisol (p<0.0001) and CRP (p<0.001) was witnessed in the stressed group.

Conclusion:

Our results demonstrate that chronic unpredictable stress exposure has affected neurogenesis in prefrontal cortex and hippocampal regions. Decreased neurogenesis was well in coordinance with the increase in cortisol and CRP. The chronic unpredictable stress-induced inflammatory response correlated to various brain regions might provoke insights into a variety of new drugs targeting neurogenesis.

Evaluation of biomarkers of stress in chronic stress-exposed comorbid depression model Wistar rats

Background In recent years, increased stress in human life has a dual effect on brain and body physiology. Chronic stress takes a toll on physiology as well as on quality of life, ultimately leading to affective disorders. Rodent models are indispensable tools for studying the etiology and progress of depression. C-reactive protein has been proposed as a novel inflammatory marker. Methods Rats were divided into control and experimental stress groups (n = 6 each). The experimental group consisted of rats that were exposed to a set of chronic unpredictable stressors for 15 days. At the end of the 15th day, the animals were anesthetized, and blood samples were collected through cardiac puncture. Then the blood samples were analyzed for selected biochemical and oxidative stress parameters. Results Serum glutamic oxaloacetic transaminase (p < 0.0001), serum glutamic pyruvic transaminase (p < 0.001), serum malondialdehyde (p < 0.0001), total antioxidant level (p < 0.0001), and serum cortisol (p < 0.0001) were significantly increased in the stressed group when compared with the control group. C-reactive protein significantly (p < 0.0001) increased in the stressed group when compared with the control group. Conclusion Our results demonstrate that chronic unpredictable stress ameliorated depression-like behavior, which might have caused the dysregulation of the hypothalamic-pituitary-adrenal axis, causing the imbalance in the biochemical and oxidative parameters increasing the inflammatory markers. The inflammation-induced model of the chronic unpredictable stress model of comorbid depression might provide a variety of new targets for antidepressant therapies.

Morphometric study of the semitendinosus muscle and its neurovascular pedicles in South Indian cadavers

The purpose of this study was to determine the length of the semitendinosus muscle belly and its tendon in South Indian population and to study the topography and diameter of its neurovascular pedicles. The study included 46 formalin fixed human cadaveric lower limbs. The length of the semitendinosus muscle belly and its tendon were measured. The neurovascular pedicles of the semitendinosus muscle were identified and counted. The diameter of the neurovascular pedicle was measured just before its entrance into the semitendinosus muscle. The topographical distance of the neurovascular pedicles from the origin of the semitendinosus muscle were determined. The mean length of the semitendinosus muscle belly was 332.3±36.1 mm and its tendon measured 154.8±31.9 mm. The mean diameter of the vascular pedicle was measuring 11.4±9.1 mm, just before its entrance into the semitendinosus muscle. The neurovascular pedicles, of the semitendinosus muscle were ranging between 1 and 7. The distance of the entrance of neurovascular pedicle to the semitendinosus muscle from its origin was ranging between 46 and 272 mm. It was observed that the neurovascular pedicles were highest (31%) at the range of 151-200 mm away from the ischial tuberosity. The morphometric data obtained in the present study is enlightening to the orthopedic and plastic surgeons. The topographical knowledge of the neurovascular pedicles has its implications during the harvesting of the grafts and pedicle flaps. The diameter of vessels in the pedicles is enlightening because of new method of anterior cruciate ligament reconstruction.