Cannabis sativa and/or melatonin do not alter brain lipid but alter oxidative mechanisms in female rats

Background

Lipid profile and redox status play a role in brain (dys)functions. Cannabinoid and melatonergic systems operate in the brain and contribute to brain (patho)physiology, but their roles in the modulation of brain lipid and redox status are not well-known. We studied the effect of ethanol extract of Cannabis sativa (CS) and/or melatonin (M) on the lipid profile and anti-oxidant system of the rat brain.

Methods

We randomly divided twenty-four (24) female Wistar rats into 4 groups (n = 6 rats each). Group 1 (control) received distilled water mixed with DMSO. Groups II–IV received CS (2 mg/kg), M (4 mg/kg), and co-administration of CS and M (CS + M) respectively via oral gavage between 8:00 am and 10:00 am once daily for 14 days. Animals underwent 12-h fasting after the last day of treatment and sacrificed under ketamine anesthesia (20 mg/kg; i.m). The brain tissues were excised and homogenized for assay of the concentrations of the total cholesterol (TC), triacylglycerol (TG), high-density lipoprotein cholesterol (HDL-C), nitric oxide (NO), malondialdehyde (MDA), and the activities of glucose-6-phosphate dehydrogenase (G6PD), glutathione reductase (GR), glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD), and acetylcholinesterase (AChE). One-way analysis of variance (ANOVA) was used to compare means across groups, followed by the least significant difference (LSD) post-hoc test.

Results

CS and/or M did not affect the lipid profile parameters. However, CS increased the G6PD (from 15.58 ± 1.09 to 21.02 ± 1.45 U/L; p = 0.047), GPx (from 10.47 ± 0.86 to 17.71 ± 1.04 U/L; p = 0.019), and SOD (from 0.81 ± 0.02 to 0.90 ± 0.01 μM; p = 0.007), but decreased NO (from 9.40 ± 0.51 to 6.75 ± 0.21 μM; p = 0.010) and had no effect on MDA (p = 0.905), CAT (p = 0.831), GR (p = 0.639), and AChE (p = 0.571) in comparison with the control group. M augmented the increase in G6PD (from 21.02 ± 1.45 U/L to 27.18 ± 1.81 U/L; p = 0.032) and decrease in NO (from 6.75 ± 0.21 to 4.86 ± 0.13 μM; p = 0.034) but abolished the increase in GPx (from 17.71 ± 1.04 to 8.59 ± 2.06 U/L; p = 0.006) and SOD (from 0.90 ± 0.01 to 0.70 ± 0.00 μM; p = 0.000) elicited by CS in the rat brain in comparison with the CS group.

Conclusions

CS and M do not alter brain lipid profile. Our data support the contention that CS elicits an anti-oxidative effect on the brain tissue and that CS + M elicits a pro-oxidant effect in rat brain.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42238-021-00095-9.

Role of reactive oxygen species-total antioxidant capacity status in Telfairia occidentalis leaves-associated spermatoprotective effect: a pointer to fatty acids benefit

Background The present study used reactive oxygen species (ROS)-total antioxidant capacity (TAC) score to understand the role of redox status on the effect of Telfairia occidentalis (TO) on testicular parameters. The fatty acids (FAs) components of methanol extract of TO (METO) and its fractions were also identified with gas chromatography-mass spectrometry. Methods A total of 66 male Wistar rats were randomly divided in a blinded fashion into six oral treatment groups as follows: group I (control, n=6) received 10% ethanol (vehicle for TO administration). Groups II to VI (n=12 rats each) were subdivided into two treatment subgroups (n=6 each) that received 200 mg/kg and 600 mg/kg of METO and its chloroform, petroleum ether, acetone, and ethanol fractions, respectively. All treatments lasted for 30 days. Results The major FAs detected in TO were myristic, palmitic, oleic, linoleic, linolenic, and stearic acids including their esters. Both doses of METO and its fractions increased the semen parameters, TAC and ROS-TAC scores but decreased the ROS when compared with control. Conclusions Using the ROS-TAC score, this study suggests that TO-associated improvement in semen parameters might be partly mediated by a reduction in free radical generation, and that the FAs present in TO might be involved in its spermatoprotective effect.

Melatonin prevents and ameliorates lead-induced gonadotoxicity through antioxidative and hormonal mechanisms

We investigated the effects of melatonin on sperm parameters and some biochemical markers in lead-exposed male Wistar rats. Lead (50 mg/kg bw/day) and/or melatonin (4 mg/kg or 10 mg/kg bw/day) was administered for 4 weeks, while 2-week lead exposure was preceded by or followed by 2-week treatment with both doses of melatonin in other groups. Lead reduced glutathione, catalase, adjusted testes weight, semen parameters but did not change malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase, and total antioxidant capacity. Though independent of prolactin, lead-induced gonadotoxicity was both centrally and peripherally mediated, as it reduced gonadotropin-releasing hormone and testosterone levels, while gonadotropin levels did not change significantly probably due to negative feedback by elevated estradiol. However, pre-, simultaneous, or posttreatment of lead-exposed rats with melatonin reduced MDA, SOD, and estradiol but dose-dependently increased other parameters. Conclusively, lead causes male gonadotoxicity through oxidative stress and endocrine mechanisms, and these could be dose-dependently prevented and ameliorated by melatonin.

Telfairia occidentalis Hook.f. - associated haematopoietic effect is mediated by cytokines but independent of testosterone: A preliminary report

ETHNOPHARMACOLOGICAL RELEVANCE

Telfairia occidentalis Hook.f. (TO) is popular in Nigeria for the ethnopharmacological use of its leaves to improve haematological parameters in normal and anaemic subjects. Cytokines are well-known to regulate haematopoiesis. However, their involvement in TO-associated haematopoietic effect is not known and necessitated this study.

MATERIALS AND METHODS

Twenty-five (25) male rats were randomly divided into 3 oral treatment groups as follows: Group 1 (control, n=5) received 0.2 ml/kg normal saline for 14 days. Groups 2 and 3 (n= 10 each) were subdivided into 2 (n=5) and received 100 mg/kg and 200 mg/kg of aqueous extract of TO respectively for 7 or 14 days.

RESULTS

TO had dose- and duration-dependent effects on the estimated parameters. Both doses of TO increased the RBC, WBC and erythropoietin concentrations at 14 but not 7 days. Moreover, its 100 mg/kg increased haemoglobin, neutrophil, and interleukin-3 concentrations at 7 days, while 200 mg/kg increased PCV and neutrophils at 14 days, lymphocytes at 7 days, and haemoglobin at both durations.

CONCLUSION

The haematopoietic effect of TO might be partly mediated by cytokines (interleukin-3 and erythropoietin) but independent of testosterone.

Pharmacological mechanisms involved in the analgesia induced by ethanol extract of Hybanthus enneaspermus leaves

Background

Hybanthus enneaspermus (HE) leaves are being used traditionally to relieve pain, and scientific studies have demonstrated their analgesic potential. This study attempted to elucidate the pharmacological mechanism(s) involved in the analgesic action of ethanol extract of H. enneaspermus leaves (EEHE).

Materials and methods

Forty-two male Wistar rats were separately randomized into seven groups (n=6 rats in each group) for tail immersion and formalin tests. Group I (control) received distilled water (10 mL/kg) while groups II and III received acetaminophen (the reference drug, 100 mg/kg ip) and EEHE (1000 mg/kg po), respectively. Groups IV–VII were pretreated with cimetidine (50 mg/kg ip), naloxone (5 mg/kg ip), propranolol (0.15 mg/kg ip), and prazosin (0.15 mg/kg ip), respectively, 1 hour before EEHE (1000 mg/kg po) treatment.

Results

The EEHE-induced increase in tail-flick latency was reduced by blockade of histamine and adrenergic receptors but prevented by blockade of opiate receptor in the tail-flick test. However, the EEHE-induced decrease in paw licking time was prevented only by blockade of opiate receptor but unaffected by histamine and adrenergic receptors blockers.

Conclusion

These findings suggest that the analgesic effect of EEHE in different pain types may involve different neural mechanisms and that the opioidergic pathway contributes more to EEHE-induced analgesia than the other pathways.

Effects of methanolic extract of Moringa oleifera leaves on semen and biochemical parameters in cryptorchid rats

While anti-oxidant effects of Moringa oleifera in much oxidative stress related diseases have been well reported, cryptorchidism on the other hand has been shown to cause oxidative stress. However, study is scanty on the likely role of Moringa oleifera in reducing cryptorchidism-induced oxidative stress in rats has not been studied. The present study looked into the effects of methanolic extract of Moringa oleifera leaves (MEMO) on semen and biochemical parameters in cryptorchid rats. Twenty male albino rats (200-250 g) were randomly divided into 4 groups (n=5 each). Groups A and B were sham-operated and treated with corn-oil and 200 mg/kg of MEMO respectively, while groups C and D were rendered cryptorchid and also treated with corn-oil and 200 mg/kg of MEMO respectively. Cryptorchid rats had lower testicular weight, sperm count, germ cell count, testicular superoxide dismutase (SOD) concentration, testicular total protein and higher testicular malondialdehyde (MDA) concentration compared to sham-operated rats. MEMO had no significant effect on testicular weight and MDA concentration, while it significantly increased sperm count, germ cell count, testicular SOD and total protein in the cryptorchid rats. The present study suggests that MEMO ameliorates cryptorchidism associated germ cell loss and oxidative stress.

Effects of salt-loading hypertension on nociception in rats

Background

There is on going controversy on the effect of experimentally induced hypertension on nociception. The effect of salt-loading-induced hypertension on pain was studied in male rats.

Method

Twenty-four male Sprague-Dawley rats (160–280 g) were divided into two groups. Group A (n = 12) was treated with normal-feed diet (control), while group B (n = 12) was treated with 8% salt-loaded diet for 10 weeks. After 10 weeks of the treatment, six rats each from groups A and B were used for blood pressure measurement, while the remaining six rats were used for both the tail-flick and formalin tests. Thermal and chemical pain test were assessed using tail immersion test (tail flick) and formalin test pain paradigms at onset of salt-loading diet and after 10 weeks of salt loading.

Results

Chronic administration of salt-loading diet caused significant increases (P < 0.001) in systolic blood pressure, diastolic blood pressure, and mean arterial blood pressure. Moreover, salt-loading-induced hypertension was found to significantly reduce pain sensitivity in the tail-immersion test (P < 0.001) and in the early and late phase of the formalin test (P < 0.01). However, the hypoalgesia was higher in the late phase (94.8%) than in the early phase (56.8%) of the formalin test.

Conclusion

The present study suggests that high salt-loading-induced hypertension causes hypoalgesia in rats, which might be due more to reduction in inflammatory response.

Vitamins e and C alleviate the germ cell loss and oxidative stress in cryptorchidism when administered separately but not when combined in rats

The antioxidant effects of vitamins C and E on cryptorchidism-induced oxidative stress were investigated in male Sprague-Dawley rats. Forty rats (200-250 g) were randomly divided in a blinded fashion into five groups (n = 8). Group 1 was sham operated and treated with vehicle (corn-oil, 10 mL/kg). Groups 2, 3, 4, and 5 were rendered unilaterally cryptorchid and treated with vehicle (10 mL/kg), vitamin E solution (75 mg/kg), vitamin C solution (1.25 g/kg), and combination of vitamin E (75 mg/kg) and vitamin C (1.25 g/kg) solutions, respectively. Germ cell count, superoxide dismutase (SOD), total protein (TP), and testicular weight (TW) were lower, but malondialdhyde (MDA) was higher in the cryptorchid rats than the sham-operated rats. When administered separately, vitamins C and E increased germ cell count, SOD, TP, and TW but did not reduce MDA in the cryptorchid rats when compared to the vehicle-treated cryptorchid rats. However, there was no significant difference in these parameters between vehicle-treated and combined vitamins C- and E-treated rats. This suggests that vitamins E and C alleviate the germ cell loss and oxidative stress in cryptorchidism when administered separately but not when combined in rats.