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.

Development of reverse phase-high performance liquid chromatography (RP-HPLC) method for determination of selected antihypertensive active flavonoids (rutin, myricetin, quercetin, and kaempferol) in medicinal plants found in Botswana

The aim of the study was to develop a rapid, efficient, and cheap chromatographic method for determining four selected antihypertensive active flavonoid compounds in medicinal plants in Botswana. The determination of rutin, quercetin, and kaempferol in selected medicinal plants was conducted in less than 6 min using the developed reverse phase-high performance liquid chromatography (RP-HPLC) method with a 2.7 µm Ascentis C18 express column (150 × 4.60 mm i.d) at 340, 360, and 368 nm detection wavelengths and mobile phase of methanol and 0.068% of formic acid solution in isocratic elution. Validation results showed good selectivity, linearity (r 2 > 0.99), high percentage recoveries (90.2–104.7%), and precision (% RSD < 2) for n = 3, confirming suitability of the method for determination of the investigated flavonoids in Zingiber officinale (ginger). Application of the developed RP-HPLC method was performed in selected medicinal plants (Lippia javanica ) (mosukujane), Myrothanmus flabellious (galalatshwene), and Elephantorrhiza elephantina (mositsana) used to manage hypertension by herbalists in Botswana. M. flabellious a very commonly used plant for managing hypertension was found to contain highest amounts of rutin and myricetin, whereas nothing was detected for E. elephantina.

In vitro hepatotoxicity assessment of Lippia javanica (Burm.f.) Spreng. aqueous leaf extract

Ethnopharmacological relevance: Lippia javanica leaves are popular in traditional food, medicine and for insecticidal uses in various Africa countries and North-East India. Anecdotal evidence suggests that it is safe to use but limited animal studies suggested potential toxicity at high dosages, including hepatotoxicity. Aim of the study: To screen for potential hepatotoxicity of L. javanica leaf extracts in vitro, thereby contributing to its toxicological profile for safe use in food and topical applications. Materials and methods: High content analysis techniques and fluorescent dyes were used to monitor C3A hepatocarcinoma cells for changes in morphological features that are associated with development of mitotoxicity, steatosis, oxidative stress, and lysosomal dysfunction. Results: No changes were observed in cell viability, reactive oxygen species or lysosomal content at concentrations up to 200 μg/ml in C3A cells. Mitochondrial membrane potential was reduced by approximately 10% but this effect was not dose-dependent nor was it accompanied by a reduction in mitochondrial content. A dose-dependent decrease was observed in neutral lipid content. Conclusion: The results from this in vitro study suggest that L. javanica leaf extracts is not anticipated to be hepatotoxic at concentrations in the range that is assumed for food or topical use.

The Nutrient, Mineral and Anti-Nutrient Studies of Two Indigenous South African Spices

The two South African spices named Lippia javanica (Izinziniba) and Foeniculum vulgare (Imbambosi) were studied for its proximate principles, minerals, vitamins and anti-nutrients properties. The experiment shows that L. javanica had higher figure in its lipids, fibres and carbohydrates contents. This implies that L. javanica may help the body to maintain an internal distention for proper peristaltic movement of the intestinal tract than F. vulgare will do. While, the protein, ash, moisture contents were more in F. vulgare, this may be the reason, more elemental composition were observed in it because the level of ash, moisture and protein contents determines its minerals or inorganic components. Elements such as Nitrogen (N), Potassium (K), Magnesium (Mg) and Sodium (Na) were observed to be more to mentioned few, the Ca/P levels of both plants was observed to be more than 0.5 which is the minimum ratio required for favourable calcium absorption in the intestine for bone formation. Likewise both plants shows no significant differences in its anti-nutrients levels such as the phytate, oxalate and tannin contents, but L. javanica had more of Vitamin A and E levels, compared to F. vulgare with better Vitamin C, Cyanide and Saponin contents. In general, spices have been reported to contribute to the average requirement for different nutrients. Polyphenols such as tannins have anticancer properties, so beverages such as green tea that contain large amount of these compounds might also be good for maintenance of human health despite its anti-nutrient properties. Comparatively, L. javanica has a better nutrient composition than F. vulgare.