The effect of moderate versus high intensity exercise on heart rate variability in sedentary office workers

Background: Sedentary behavior is one of the leading modifiable risk factors for cardiovascular disease and all-cause mortality. Physical exercise exerts beneficial physiological effects on cardiovascular fitness. Different grades of physical exercise have different effects on cardiovascular health. Objective: To compare the effect of moderate and high intensity exercise training on heart rate variability (HRV) in sedentary office workers. Methods: This study was conducted on 40 healthy sedentary volunteers aged between 20-40 years of both the genders. Participants were distributed into two groups of 20 subjects each. Subjects of group I and group II performed moderate intensity and high intensity exercise respectively on bicycle ergometer for 12 weeks. Their 5- minute ECG recording was done by three channel physiograph, and frequency domain indices of HRV and heart rate (HR) were analyzed and compared before and after exercise training. Their blood pressure was also recorded and compared before and after exercise training. Independent sample t-test and paired sample ttest were used for statistical analysis. Results: HF, systolic and diastolic blood pressure reduced significantly after exercise in group II (p=0.015, 0.005, and 0.015 respectively) while HR and LF/HF ratio reduced in both group I and group II (p=0.000 for HR, and 0.034, 0.001 for LF/HF). The decrease in HR was greater after high intensity exercise than moderate intensity exercise (p= 0.025). Conclusion: Parasympathetic activity improves after moderate and high intensity exercise but improvement is more after high intensity exercise training. Therefore, high intensity exercise training is more beneficial than moderate intensity exercise training. J Bngladesh Soc Physiol 2021;16(1): 16-23

Effects of Spirulina platensis on neuropathic pain in Wistar rats

Background: In treatment of neuropathic pain, conventional analgesics showed various adverse effects. Spirulina platensis (Sp), a medicinal herb, shown to possess several beneficiary biological activities including analgesic, anti-inflammatory and anti-ulcerogenic potential. Objectives: To assess the effect of Sp on neuropathic pain in Wistar rats and also to assess the involvement of ATP sensitive potassium channel (KATP) as its possible underlying mechanism of action. Methods: For this experimental study 120 Wistar rats of both sexes (200±50 gm body weight) were grouped into control [normal saline (NS) 5 ml/kg/day], sham control [sham surgery + NS], CCI control [Chronic constriction injury to sciatic nerve (CCI) + NS], Sp experimental [CCI + Sp 400 mg/kg/day], Gli experimental [CCI + Sp (400 ml/kg/day) + glibenclamide (15 mg/kg)] groups. Sp and NS were administered orally once daily for consecutive 21 days and single dose of glibenclamide was given intraperitoneally. Then again on the basis of neuropathic pain evaluation tests, all the groups were subdivided into ‘a’ (for walking track analysis), ‘b’ (for cold tail immersion test), ‘c’ (for von Frey test), ‘d’ (for hot plate test). The statistical analysis was done by one-way ANOVA followed by Bonferroni post hoc test, where P£0.05 was considered as statistically significant. Results: In this study, Sp showed significantly (P£0.001) higher sciatic functional index, tail flick latency, paw withdrawal threshold and reaction time in Sp experimental rats compared to those of CCI control rats. In addition, there were significant (P£0.001) differences in the above-mentioned variables between rats of Sp experimental group and Gli experimental group. Conclusion: From the present study it could be concluded that, Spirulina platensis prevents the development of neuropathic pain in Wistar rats through opening of KATP channel. J Bngladesh Soc Physiol 2021;16(1): 1-10

Effects of omega-3 fatty acid supplementation on serum Alanine Transferase and Aspartate Transferase levels in middle-aged patients with type 2 diabetes mellitus

Background: People with type2 diabetes mellitus (DM) are at amplified chance of non-alcoholic fatty liver disease. Objective: To observe the effects of omega-3 fatty acid supplementation Alanine Transferase (ALT) and Aspartate Transferase (AST) in middle age patients with type 2 DM. Methods: A prospective interventional study in 2017, recruited 52 type 2 diabetic patients of both sexes aged 40 to 50 years. Among them, 27 patients were given fish oil capsule orally (omega 3 fatty acid 2g/day) for consecutive 12 weeks and 25 patients without supplementation were selected as control also studied after 12 weeks. Serum ALT and AST of all patients were estimated by enzymatic colorimetric method at baseline and after 12 weeks. For statistical analysis, Paired Student’s ‘t’ test and Unpaired Student’s ‘t’ test were performed. Results: In this study ALT and AST significantly decreased in patients supplemented with omega-3 fatty acid after 12 weeks, ALT (alanine aminotransferase) and AST (aspartate transaminase) were decreased in diabetic patients after supplementation with omega- 3 fatty acid in comparison to control group. Conclusion: It can be concluded that omega-3 fatty acid supplementation was effective to reduce ALT and AST levels in diabetic patients and it may be helpful to minimize the risk of fatty liver in type-2 DM. J Bngladesh Soc Physiol 2021;16(1): 39-43

Students teaching students: Can medical students play a part in undergraduate physiology teaching?

Over the past decade active and self-directed learning has been given precedence in medical curricula. At the Faculty of Medical Sciences, University of Sri Jayewardenepura, Sri Lanka, a novel approach was trialed to teach applied physiology using a student-seminar, where the teaching content was developed by the medical students. Clinically relevant physiology topics were randomly allocated to ten studentgroups. Each group had to deliver their findings to peers and academic tutors during a seminar, using audiovisual aids. This study aimed to explore student perceptions regarding this novel learning experiment. Student perceptions of the seminar were explored using self-administered surveys and were rated. Analysis of subject-related knowledge showed that marks of the participants (n=125) had increased significantly, on average by 13% (t110= -8.878 p<0.001). Majority of students didn’t perceive the student seminar as satisfactory for teaching Applied Physiology. However, student seminars seem to be a useful way to enhance group learning and active self-directed learning. J Bngladesh Soc Physiol 2021;16(1): 57-60

Nephroprotective effect of Aloe barbadensis Miller against gentamicin induced nephrotoxicity in long evans male rats

Background: Kidney is an essential excretory organ of our body. It can be damaged by poisonous effect of chemicals, toxin, prolonged and uncontrolled use of drugs. Aloe vera is a herbal plant, it can be used for the prevention and treatment of kidney damage due to its natural compatability. Objective: To observe the nephroprotective effect of Aloe vera against gentamicin induced nephrotoxicity in long evans male rats. Method: This experimental study was conducted in the Department of Physiology, Sir Salimullah Medical College (SSMC), Dhaka from 1st January 2018 to 30th December 2018. For this, forty five (45) apparently healthy long evans male rats, 90-120 days old, weighing between 150-200 g were taken and divided into control group (group A) and experimental group (group B - Aloe vera pretreated and gentamicin treated group). Control group was subdivided into group A1 (baseline control group) and group A2 (gentamicin treated control group). Each group consisted of fifteen (15) rats. At the beginning of the study period initial body weight of rats were measured at day 01. All the rats received basal diet for thirty (30) days. Group A1 received only basal diet for 30 consecutive days (started from day 1 to day 30). In addition to basal diet, group A2 received injection gentamicin intraperitoneally once daily in the morning (80 mg/kg/day) for last 5 days (26th to 30th) of the study period. Again, in addition to basal diet, experimental group received Aloe vera orally (200 mg/kg/day) for 30 days and injection gentamicin intraperitoneally (80 mg/kg/day) for last 5 days (26th to 30th). After measuring final body weight all the rats were sacrificed on day 31. Blood sample was collected from heart. Serum levels of creatinine and urea were estimated for assessment of kidney function. Statistical analysis was done by one way ANOVA test followed by post hoc-Bonferroni test. Result: Mean serum levels of creatinine and urea were significantly (p<0.001) higher in gentamicin treated control group in comparison to that of base line control group. Again these levels were significantly (p<0.001) lower in Aloe vera pretreated and gentamicin treated group than that of gentamicin treated control group. Conclusion: From this study, it is concluded that Aloe vera has nephroprotective effect against gentamicin induced nephrotoxicity. J Bngladesh Soc Physiol 2021;16(1): 33-38

Effects of hyperthyroidism on serum alanine amino transferase and alkaline phosphatase levels in liver

Background: Hyperthyroidism is one of the most common endocrine disorders. Thyroid hormones are essential for normal metabolic function of body cells including the liver cells. Again, metabolism of thyroid hormones takes place in liver. Therefore, hyperthyroidism may affect liver cells and causes change in hepatic enzymes level. Objective: To assess serum alanine aminotransferase (ALT) and alkaline phosphatase (ALP) levels in hyperthyroid patients. Methods: This cross sectional study was conducted in the Department of Physiology of Dhaka Medical College from July 2016 to June 2017. Total number of 50 subjects of both sexes aged from 18 to 50 years were selected. Among them, 25 hyperthyroid patients were considered as the study group (B) and 25 age matched healthy subject were considered as control group (A). Serum ALT and ALP were estimated in the Biochemistry & Molecular Biology Department of BSMMU. For statistical analysis, Unpaired student’s ‘t’ test and Chi Square test were done. Results: Serum ALT and ALP levels were significantly (p<0.001) increased in patients suffering from hyperthyroidism. Conclusions: This study showed that detection of changes in serum hepatic enzymes in hyperthyroidism useful for prediction of developing liver disease. J Bngladesh Soc Physiol 2021;16(1): 44-48

Acute ST-Elevation Myocardial Infarction Associated with Metabolic Syndrome and Its Angiographic Outcome

Background: Metabolic Syndrome is already one of the major public health problems around the world; it may be more grievous when associated with any cardiac emergency like myocardial infarction (MI). Objective: To evaluate the association of metabolic syndrome and its angiographic effects on patients with Acute ST-Elevation Myocardial Infarction (acute STEMI). Methods: This prospective observational study was done in the Department of Cardiology of the National Institute of Cardiovascular Diseases (NICVD), Dhaka, Bangladesh, between July and December of 2013. A total 233 patient were selected for data collection; of them 109 were in group I (acute STEMI patients with metabolic syndrome) and 124 in group II (acute STEMI patients without metabolic syndrome). Initial evaluation of the patients was done by history taking and clinical examination. Baseline investigations like ECG, CK(MB), lipid profile, fasting blood sugar, serum creatinine and echocardiography were done. Coronary angiogram (CAG) was done in the Cardiac Cath-Lab facility of the same hospital. Data was analyzed by using SPSS version 16.0. Comparison between groups was done by unpaired t-test, while categorical data was analyzed with Chi-square (c2) test. Results: In patients with metabolic syndrome (group I), most of them (68.9%) had more than 2 metabolic components out of 4; the combinations were: high TG + low HDL (54.6%), DM + high TG (46.9%), raised BP + high TG (38.5%), DM + low HDL (33.6%), raised BP + low HDL (26.4%) and raised BP and DM ( 24.3%).ECG shows that the inferior wall acute myocardial infarction (MI) was 41.28% and 44.55% in group I and group II respectively, while anterior wall was involved 58.71 % and 55.65% cases respectively, which was not statistically significant. Heart failure was significantly more in patients of group I than group II (46.79% vs. 20.97%; p<0.001). Echocardiography reveals that the left ventricular (LV) ejection fraction (EF) was much less in group I than that of group II (42.8±18.07% vs. 50.4±21.2%; p<0.001). Among the patients who underwent coronary angiogram (CAG), the mean Friesinger score were 9.7±2.5 in group I and 7.1±3.3 in group II (p<0.05); it indicated more chances of severe coronary artery disease and fatality in group I patients. Conclusion: Acute ST-elevation myocardial infarction patients with metabolic syndrome have much worse angiographic outcome and poor prognosis than those without metabolic syndrome. J Bngladesh Soc Physiol 2021;16(1): 49-56

Effect of Slow Breathing Exercise on some cardio vascular functions in Type 2 Diabetic Male Patients

Background: Slow breathing exercise (SBE) has some useful effects on cardiovascular system. Objectives: To observe the effects of slow breathing exercise on blood pressure in male patients with type 2 diabetes mellitus (DM). Methods: This interventional study was implemented on sixty (60) diagnosed male type 2 diabetes mellitus (T2DM) patients aged 45-55 years with disease history 5-10 years, selected from Out Patients Department (OPD) of Endocrinology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka. The subjects were divided into two groups, control group (n=30) included type 2 DM patients without SBE and study group included patients performing SBE for 3 months(n=30) and they were enrolled bypurposive sampling method. The study group was advised to practice SBE for 30 minutes 2 times daily for 3 months. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure(MAP),pulse pressure(PP) and rate pressure product (RPP)were recorded at the start of the study and after 3 months in both group of patients.. Independent sample t test and paired sample t-test were used for statistical analysis and p<0.05 was taken as statistical significance. Results: In this study, the value of mean HR, SBP, DBP, MAP and RPP were significantly (p<0.05) reduced after 3 months of SBE. Again no significant changes observed (p>0.05) after 3 months in the group who did not practice SBE. Conclusion: Cardiovascular functions in T2DM patients was improved after performing slow breathing exercise for 3 months. J Bngladesh Soc Physiol 2021;16(1): 11-15

Vitamin B12, Folic acid and Homocysteine Levels in female metabolic syndrome patients and their relationship with Heart rate variability.

Background: Metabolic syndrome (MeS) is a well-recognized risk factor for cardiovascular diseases. It is associated with hyperhomocysteinemia resulting from deficiency of vitamin B12 and folic acid. Both the MeS and hyperhomocysteinemia adversely affect heart rate variability. Objectives: To assess vitamin B12, folic acid and homocysteine levels in female metabolic syndrome patients and their relationship with heart rate variability. Methods: After taking ethical clearance from Institutional Review Board (IRB) of Bangabandhu Sheikh Mujib Medical University (BSMMU) this cross sectional study was conducted on 80 female subjects of 25-45 years of age. Among them 40 metabolic syndrome patients were included in the study group and 40 age matched apparently healthy female constituted control group. All the patients were enrolled from Outpatient Department of Endocrinology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh according to selection criteria. Serum vitamin B12, folic acid, homocysteine level was estimated by chemiluminescent immunoassay and frequency domain parameters of Heart Rate Variability (HRV) was recorded by a data acquisition device, Powerlab 8/35, AD instruments, Australia. Statistical aalysis was done by independent sample ‘t’ test and pearson correlation test. Results: In this study, among frequency domain HRV variables Total power(TP), low frequency power(LF), high frequency power (HF), HF normalized unit(nu) were significantly lower (p<0.05) and LF nu, LF/HF were significantly higher (p<0.05) in MS patients compared to those of control. In addition, no significant changes (p>0.05) were found in serum vitamin B12, folic acid and homocysteine levels between these two groups. But on correlation analysis only the folic acid level was significantly negatively correlated (p<0.05) with LF and HF power. Conclusion: The present study revealed that the folic acid level but not the vitamin B12 and homocysteine levels has significant negative correlation with heart rate variability in female MS. J Bngladesh Soc Physiol 2021;16(1): 24-32

Morphometric study of the size of the postmortem human kidney

Background: Changes in the size of the kidney are evident in humans, as age progresses. Objective: To see the age-related changes in the morphological dimensions of the kidney in a sample of the Bangladeshi population. Methods: This crosssectional study was done in the Department of Anatomy, Dhaka Medical College, Dhaka, from July 2008 to June 2009, based on a collection of 140 postmortem human kidneys collected from 70 unclaimed dead bodies from the morgue of the same institution. All the samples of kidney were divided into three age groups, including A (10-19 years), B (20-39 years) and C (40-59 years). The length, breadth and thickness of all the kidneys were measured by using a slide calipers and recorded. Data were expressed as mean±SD. For statistical analysis, independent sample t test and one way ANOVA was used. Results: The length of the right and left kidneys found were 8.72±0.25 cm and 9.28±0.12 cm; 9.73±0.35 cm and 10.31±0.41 cm; 9.68±0.21 cm and 10.24±0.06 cm in group A, B and C respectively. The breadth of the right and left kidneys found were 4.32±0.09 cm and 4.22±0.11 cm; 4.74±0.29 cm and 4.55±0.28 cm; 4.61±0.21 cm and 4.44±0.21 cm in group A, B and C respectively. The thickness of the right and left kidneys found were 2.84±0.10 cm and 2.64±0.05 cm; 3.31±0.16 cm and 3.11±0.10 cm; 3.17±0.07 cm and 3.11±0.10 cm in group A, B and C respectively. The mean length of the left kidneys was found significantly greater than that of the right , whereas the mean breadth and the thickness of the right kidneys were found greater than that of the left kidney in all age groups. Moreover, age related changes were significant in all dimensions (length, breadth and thickness) of the kidney when compared between group A & B and A & C. Conclusion: This study results concluded that the length of the left kidney was greater than that of the right, but the breadth and the thickness of the right kidney were greater than that of the left one in all age groups. In addition, age related changes in all dimensions (i.e. length, breadth and thickness) of the kidneys were evident in middle age versus young adult and older adult versus young adult. J Bangladesh Soc Physiol. 2020, December; 15(2): 61-67