Comparative study of antipyretic potency of extracts of morinda lucida leaves and fruits of capsicum frutescens in albino rats.

Background: Morinda lucida leaves and fruits of Capsicum frutescens are used locally in the management of fever in Nigeria. No scientific credence has been lent to this claim. Objective: To investigate the antipyretic effect and potency of aqueous extracts of Morinda lucida leaves and fruits of Capsicum frutescens in albino rats. Method: Brewer's yeast was used to induce pyrexia. Thirty animals were divided into six groups. Group A was orally administered normal saline (103 mg/kg). Group B was served indomethacin (5 mg/kg), while groups C and D received aqueous extract of Capsicum frutescens at 100mg/kg and 200mg/kg, 17 hours post induction of pyrexia. Groups E and F were administered extract of Morinda lucida at the same doses. Rectal temperature of the animals was taken at 60-, 90- and 120-minutes post-treatment. Results: Both C. frutescens and M. lucida produced significant reduction (p<0.05) in rectal temperature after 120 minutes in the rats compared with animals in the control group. Also, the antipyretic activities of the two extracts at 100mg/kg and 200mg/kg were comparable to 5mg/kg of indomethacin, with apparent dose dependence in the antipyretic activities of both extracts. Conclusion: Morinda lucida leaves and fruits of Capsicum frutescens exhibit dose-dependent antipyretic activities.

Bromelain reduced pro-inflammatory mediators as a common pathway that mediate antinociceptive and anti-anxiety effects in sciatic nerve ligated Wistar rats.

The involvement of pro-inflammatory mediators complicates the complex mechanism in neuropathic pain (NP). This study investigated the roles of bromelain against pro-inflammatory mediators as a mechanism that underpins its antinociceptive and anti-anxiety effects in the peripheral model of NP. Sixty-four male Wistar rats randomly divided into eight groups, were used for the study. A chronic constriction injury model of peripheral neuropathy was used to induce NP. Tail-immersion and von Frey filaments tests were used to assess hyperalgesia while open field and elevated plus mazes were used to assess anxiety-like behaviour. NF-кB, iNOS, nitrate, and pro-inflammatory cytokines were investigated in the plasma, sciatic nerve, and brain tissues using ELISA, spectrophotometer, and immunohistochemistry techniques after twenty-one days of treatment. Bromelain significantly (p < 0.05) improved the cardinal signs of NP and inhibited anxiety-like behaviours in ligated Wistar rats. It mitigated the increases in cerebral cortex interleukin (IL) -1ß, IL-6, and PGE2 levels. Bromelain reduced NF-кB, IL-1ß, IL-6, TNF-α, PGE2, and nitrate concentrations as well as the expression of iNOS in the sciatic nerve. Hence, the antinociceptive and anxiolytic effects of bromelain in the sciatic nerve ligation model of NP is in part due to its ability to reduce nitrosative and inflammatory activities.

Analgesic properties of aqueous bark extract of Adansonia digitata in Wistar rats.

The study investigated the analgesic effect of the aqueous extract of the bark of Adansonia digitata using Wistar rats. Thirty Wistar rats weighing between 150 and 170g of either sex were used for the study. Animal were picked randomly and grouped into six with each group made up of five animals (3 females and 2 males). Oral administration of 10ml/kg of normal saline were given to control group; 5mg/kg of indomethacin to reference group; and 25mg/kg, 50mg/kg, 100mg/kg or 200mg/kg of aqueous extracts of Adansonia digitata to each of the test groups respectively.Hotplate and formalin paw-licking tests were used for nociceptive assessment. Animals treated with aqueous bark extract of Adansonia digitata showed significantly (p<0.05) prolonged response time to thermal stimuli (4.42±0.11s) compared with control group (3.29±0.29s) in a dose dependent manner. Results formalin paw-licking test showed that at early phase, animals administered with aqueous bark extract of Adansonia digitata significantly (p<0.05) have reduced paw-licking time (47.88±3.48-40.80±3.85s) compared with the control group (91.51±7.32s). In the late phase, aqueous bark extract of Adansoni adigitata significantly (p<0.05) reduced the paw-licking time (43.57±2.6-25.49±3.46s) compared with the control group (66.31±5.04s). It is hereby concluded that aqueous bark extract of A. digitata possesses a strong analgesic effect.

Anti-inflammatory and antipyretic properties of Corchorus olitorius aqueous root extract in Wistar rats.

BACKGROUND: This study was designed to provide information about the antipyretic and anti-inflammatory effects of Corchorus olitorius root. METHODS: Thirty male Wistar rats were divided into six groups of five animals each; the control and reference groups were administered normal saline (10 mL/kg) and indomethacin (5 mg/kg), respectively, whereas the remaining four groups were administered aqueous extract of C. olitorius at doses of 25, 50, 100, or 200 mg/kg, respectively. Pyrexia was induced by injecting 10 mL/kg of 20% (w/v) brewer's yeast suspension into the dorsum of rats, whereas inflammation was induced through an injection of 0.1% carrageenan into the right hind paw of each rat and through a subcutaneous implantation of a 30-g sterilized cotton pellet into the groin of each rat. RESULTS: The results showed that C. olitorius root extract (p<0.05) decreased the elevated temperature after brewer's yeast injection compared with the 17 h (pre-drug) temperature. In the inflammatory tests, the paw sizes and granuloma weights in the test groups were significantly (p<0.05) decreased compared with the control group. CONCLUSIONS: Corchorus olitorius root is another good source of phytomedicine that can be used effectively to treat inflammation and pyrexia that accompany some diseases.

Analgesic and anti-inflammatory effects of aqueous extract of Zea mays husk in male Wistar rats.

The analgesic and anti-inflammatory activities of Zea mays husk extract (25, 50, 100, and 200 mg/kg of body weight) were investigated in rats. The hot plate and formalin-induced paw licking models were used to assess analgesic effects of the extract, whereas the carrageenan and cotton pellet models were used for the evaluation of anti-inflammatory activity. The extract at 25, 50, 100, and 200 mg/kg body weight significantly (P < .05) reduced pain stimuli and inflammatory activity when compared with the control group. The reductions in paw licking time and granuloma weight in the formalin and cotton pellet models were both dose dependent. Also, the 200 mg/kg doses of the extract produced higher effects compared with indomethacin (5 mg/kg body of weight) in all the tests. These observations suggest that Z. mays husk extract may have analgesic and anti-inflammatory effects that may be due to its tannins and polyphenolic constituents. These results provide scientific validation for the use of Z. mays husk decoction for the treatment of pain and inflammatory conditions in Nigerian folk medicine.

Studies on the analgesic, anti-inflammatory and antipyretic effects of Parquetina nigrescens leaf extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Parquetina nigrescens is a shrub that is commonly used in different parts of West Africa for the treatment of several ailments which includes pain, fever and inflammatory conditions. AIM OF THE STUDY: The present study was designed to investigate the analgesic, anti-inflammatory and antipyretic effects of the aqueous extract of Parquetina nigrescens leaves in rats. MATERIALS AND METHODS: Five groups were used for each study, groups 1 and 5 served as control (saline) and reference (indomethacine) respectively, while groups 2-4 received the extract (50-200 mg/kg) orally. Formalin paw licking and hot plate latency tests were used for analgesic studies. Carrageenan oedema, cotton pellet granuloma and formaldehyde arthritis models were used to quantify the anti-inflammatory activities while the brewer's yeast was used for inducing pyrexia. RESULTS: The results of the analgesic study show that the extract produced significant (p<0.05) analgesia in the hot plate and in the formalin tests. In the anti-inflammatory study, Parquetina nigrescens produced significant (p<0.05) inhibition of the various types of inflammation. The extract also inhibited the pyrexia induced by brewer's yeast. CONCLUSION: The result justifies the traditional uses of Parquetina nigrescens for the treatment of fever, inflammatory and painful conditions.

Anti-inflammatory activities of ethanolic extract of Carica papaya leaves.

The anti-inflammatory activity of an ethanolic extract of Carica papaya leaves was investigated in rats using carrageenan induced paw oedema, cotton pellet granuloma and formaldehyde induced arthritis models. Experimental animals received 25-200 mg/Kg (orally) of the extracts or saline (control group) and the reference group received 5 mg/ Kg of indomethacin. The ulcerogenic activity of the extract was also investigated. The results show that the extracts significantly (p <0.05) reduced paw oedema in the carrageenan test. Likewise the extract produced significant reduction in the amount of granuloma formed from 0.58 +/-0.07 to 0.22 +/-0.03 g. In the formaldehyde arthritis model, the extracts significantly reduced the persistent oedema from the 4th day to the 10th day of the investigation. The extracts also produced slight mucosal irritation at high doses. The study establishes the anti-inflammatory activity of Carica papaya leaves.