Neuroprotective effects of Lippia javanica (Burm.F.) Spreng. Herbal tea infusion on Lead-induced oxidative brain damage in Wistar rats.

BACKGROUND: Though Lippia javanica (Burm.f.) Spreng antioxidant activity has been demonstrated, its effect in protecting the brain from lead (Pb)-induced oxidative damage is unknown. This study investigated the effect of L. javanica against Pb-induced oxidative stress, inflammation, apoptosis and acetylcholinesterase activity in rat's brain. METHODS: L. javanica herbal tea infusion was prepared, its phytochemical constituent was revealed by liquid chromatography-Mass spectrometer (LC-MS) and was administered simultaneously with Pb. Four groups of male Wistar rats (n = 5/group) were used: control received distilled water; Pb-acetate group received 50 mg Pb/ Kg bodyweight (bw), treatment group received 50 mg Pb/ Kg Pb-acetate + 5 ml/kg bw L. javanica and L. javanica group received 5 ml/Kg bw of L. javanica tea infusion only. After 6 weeks of treatment, oxidative status, acetylcholinesterase activity, inflammation and apoptosis was assessed in brain tissue which was also histologically examined. RESULTS: Mean brain and heart weight was reduced (p < 0.05) while liver and spleen weights were increased (p < 0.05) in Pb exposed animals but were prevented by L. juvanica treatment. Treatment with L. javanica increased (p < 0.05) overall brain antioxidant status (glutathione and superoxide dismutase activities) and reduced lipid peroxidation (p < 0.05) compared to the Pb exposed animals. Pro-inflammatory cytokine tumour necrotic factor-alpha, pro-apoptosis Bax protein and anticholinesterase activity were reduced (p < 0.05) in Pb-L. javanica treated animals compared to the Pb exposed group. Histological examination confirmed neuroprotective effects of L. javanica as evidenced by reduced apoptosis/necrosis and inflammation-induced vacuolization and oedema in the hippocampus. The L. javanica treatment alone had no detrimental effects to the rats. LC-MS analysis revealed L. javanica to be rich in phenolics. CONCLUSIONS: This study demonstrated that L. javanica, rich in phenolics was effective in reducing Pb-induced brain oxidative stress, inflammation, apoptosis, acetylcholinesterase activity and neuronal damage.

Lippia javanica (Zumbani) herbal tea infusion attenuates allergic airway inflammation via inhibition of Th2 cell activation and suppression of oxidative stress.

BACKGROUND: Lippia javanica (lemon bush) is commonly used in the treatment of respiratory ailments, including asthma in southern African countries but there is no scientific evidence to support this claim. This study investigated the anti-inflammatory, antioxidant and anti-asthmatic effects of L. javanica using a rat model of asthma. METHODS: A 5% w/v L. javanica tea infusion was prepared and characterised by liquid chromatography-mass spectrometer (LC-MS). Animals were intraperitoneally sensitized with ovalbumin (OVA) and subsequently challenged intranasal with OVA on day 15 except the control group. Animals were grouped (n = 5/group) for treatment: unsensitised control, sensitised control, sensitised + prednisolone and sensitised + L. javanica at 50 mg/kg/day and 100 mg/kg/day - equivalent to 1 and 2 cups of tea per day, respectively. After 2 weeks of treatment, bronchoalveolar lavage fluid (BALF) was collected for total and differential white blood cell (WBC) count. Nitric oxide (NO), lipid peroxidation and antioxidants were also assessed in BALF. Ovalbumin specific IgE antibody and inflammatory cytokines: IL-4, IL-5, IL-13 and TNF-alpha were measured in serum. Lung and muscle tissues were histological examined. RESULTS: L. javanica was rich in phenolic compounds. OVA sensitisation resulted in development of allergic asthma in rats. L. javanica treatment resulted in a reduction in total WBC count as well as eosinophils, lymphocytes and neutrophils in BALF. L. javanica inhibited Th2-mediated immune response, which was evident by a decrease in serum IgE and inflammatory cytokines: IL-4, IL-5, IL-13 and TNF-α. L. javanica treatment also reduced malondialdehyde (MDA) and NO, and increased superoxide dismutase, glutathione and total antioxidant capacity. Histology showed significant attenuation of lung infiltration of inflammatory cells, alveolar thickening, and bronchiole smooth muscle thickening. CONCLUSION: L. javanica suppressed allergic airway inflammation by reducing Th2-mediated immune response and oxidative stress in OVA-sensitized rats which may be attributed to the presence of phenolic compound in the plant. This finding validates the traditional use of L. javanica in the treatment of respiratory disorders.

Senecio serratuloides extract prevents the development of hypertension, oxidative stress and dyslipidemia in nitric oxide-deficient rats.

Background Hypertension is a silent killer with no obvious signs and symptoms; thus, it is crucial to prevent its development. Oxidative stress and hyperlipidemia are associated risk factors for developing hypertension. This study aimed at investigating the role of a crude extract of Senecio serratuloides in preventing the development of hypertension, oxidative stress and hyperlipidemia in a rat model of nitric oxide deficiency. Methods Female Wistar rats were co-treated with Nω-Nitro L-arginine methyl ester (L-NAME) (40 mg/kg) and the hydroethanolic extract of S. Serratuloides (HESS150 or HESS300 mg/kg) for 4 weeks. Twenty-hour urine samples were collected weekly during the study. At the end of the study serum, heart and kidneys were harvested for biochemical and histopathological analysis. Results The higher dose (300 mg/kg) of the extract was more effective in preventing increase in systolic (p<0.001) and diastolic (p<0.05) blood pressure. At the end of the treatment period HESS300 treated rats had significantly (p<0.01) higher concentration of creatinine (91.24 ± 6 mg/dL) in urine and significantly (6.36 ± 0.4 mg/24 h; 0.001) lower proteinuria compared to L-NAME control rats (55.75 ± 8 mg/dL and 18.92 ± 2 mg/24 h, respectively). Creatinine clearance and glomerular filtration rate were lower in the L-NAME control group compared to all treatment groups. HESS300 prevented L-NAME-induced decrease in serum angiotensin II concentration, significantly decreased malondialdehyde concentration in serum (p<0.05) and kidneys (p<0.001). It also significantly (p<0.001) decreased low-density lipoprotein concentration while increasing the concentration of high-density lipoprotein cholesterol. It showed cardio- and reno-protective effects and significantly (p<0.01) prevented collagen deposition in these target organs. Conclusion These findings demonstrate the potential of S. Serratuloides in protecting rats from developing hypertension, hyperlipidemia and oxidative stress.

The protective effect of aqueous extract of Typha capensis rhizomes on cadmium-induced infertility in rats.

Background Typha capensis is one of the medicinal plants commonly used to manage male fertility problems. The objective of the present study was to assess its fertility-promoting effects in a rat model of cadmium-induced infertility. Methods A total of 30 male Wister rats were randomly divided into five groups of six animals each. Animals of group I, which served as control, were administered with cadmium chloride (CdCl2; 2.5 mg/kg) and normal saline (2 mL/kg). Group II was served with 0.5 mL normal saline only. Animals of groups III-V were treated with CdCl2 (2.5 mg/kg) plus T. capensis extract at doses of 100, 200, and 400 mg/kg, respectively. Animals were sacrificed under sedation. Testes and epididymal weights and sperm count were determined. Histological assessment of the testes was conducted. Results T. capensis at any dose did not improve (p > 0.05) testicular and epididymal weights compared with those of the CdCl2-exposed control group. Histology revealed moderate necrosis in the same group. T. capensis modestly increased the sperm count by 14%, 31%, and 35%, for groups treated with the extract at doses 100, 200, and 400 mg/kg, respectively, when compared with the CdCl2 control group, although the differences were not significant statistically (p > 0.05). Conclusions Results of our study demonstrated that T. capensis can neither offer protective effects against oxidative stress nor promote fertility in an animal model of cadmium-induced infertility.