A Vegetable, Launaea taraxacifolia, Mitigated Mercuric Chloride Alteration of the Microanatomy of Rat Brain

Mercury chloride causes cognitive impairment, oxidative stress and neuroinflammation in male Wistar rats: The potential protective effect of 6-gingerol-rich fraction of Zingiber officinale via regulation of antioxidant defence system and reversal of pro-inflammatory markers increase

This study investigated the effects of 6-gingerol-rich fraction of Zingiber officinale (6-GIRIFZO) on mercury chloride (HgCl2)-induced neurotoxicity in Wistar rats. Thirty -five male Wistar rats weighing between (150-200 g) were divided randomly into five groups (n = 7): group 1: control, received 0.5 mL of normal saline, group 2: received HgCl2 (5 mg/kg), group 3: received N-acetylcysteine (NAC) (50 mg/kg) as well as HgCl2 (5 mg/kg), group 4: received 6-GIRIFZO (100 mg/kg) and HgCl2 (5 mg/kg), group 5: had 6-GIRIFZO (200 mg/kg) and HgCl2 (5 mg/kg), consecutively for 14 days. On the day14, the rats were subjected to behavioural tests using a Morris water maze and novel object recognition tests. The rats were then euthanized to obtain brain samples for the determination of biochemical parameters (acetylcholinesterase (AchE), nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione (GSH), tumor necrosis factor- alpha (TNF-α), nuclear factor kappa-B (NF-κB), interleukin-1β (IL-1β) and interleukin-6 (IL-6)) using standard methods. The result revealed a significant increase in escape latency and a significant decrease in recognition ratio in the rats that were exposed to HgCl2 only. However, 6-GIRIFZO produced a significant reduction in the escape latency and (p < 0.05) increase in the recognition ratio. Similarly, HgCl2 exposure caused a significant (p < 0.05) decrease in the brain SOD, GPx, CAT, GSH with increased brain levels of MDA, NO, AchE, TNF-α, NF-κB, IL-1β and IL-6. Similarly to the standard drug, NAC, 6-GIRIFZO (100 and 200 mg/kg) significantly (p < 0.05) increased brain SOD, GPx, CAT, and GSH levels with decreased concentrations of MDA, NO, AchE, TNF-α, NF-κB, IL-1β and IL-6. Also, pre-treatment with 6-GIRIFZO prevented the HgCl2-induced morphological aberrations in the rats. This study concludes that 6-GIRIFZO prevents HgCl2-induced cognitive deficit via reduction of brain inflammation as well as oxidative stress in rats.

Amelioration of mercuric chloride-induced physiologic and histopathologic alterations in rats using vitamin E and zinc chloride supplement

The drastic effects of mercuric chloride and the protective efficiency of vitamin E and zinc chloride co-supplementation were clearly investigated in this study. Male rats were divided into four groups. The first was the control. The second received vitamin E (100 mg/kg) and zinc chloride (30 mg/kg) daily. In comparison, the third received mercuric chloride (1 mg/kg) daily, and the fourth received the same mercuric chloride dose supplemented with the same vitamin E and zinc chloride doses. Mercury promotes a significant decline in body weight. It causes a considerable reduction in total red blood cells (RBCs) count and hemoglobin concentration; however, white blood cells (WBCs) increased significantly. Significant mercury-induced elevations in hepatic and renal functions were observed. Mercury induced substantial reductions in catalase (CAT) and superoxide dismutase (SOD). Mercury caused apoptotic DNA fragmentation. It induced degeneration and necrosis in the liver and kidney. It induced necrosis, leukocyte infiltration and blood vessel congestion in the cerebral cortex. Shrinkage and deterioration of Purkinje cells of the cerebellum were observed in response to mercuric chloride toxicity. Mercuric chloride enhanced shrinking in seminiferous tubules and Leydig cells. It reduced sperm count, sperm motility, and testosterone concentration; however, it promoted abnormal sperm morphology. Administration of vitamin E and zinc chloride showed marked improvement in different parameters under investigation, however, further research is needed to determine fate of mercury.

Andrographis paniculata protects against brain hippocampus and cerebellum from mercury chloride induced damage by attenuating oxidative stress

Mercury chloride (HgCl2) is a neurotoxicant that remains a health hazard despite numerous efforts to reduce its levels in the environment. The use of medicinal plants in treating various diseases and other toxic agents has grown popular owing to their effectiveness and affordable rates. Andrographis paniculata (A. paniculata) is a plant with astringent and detoxifying characteristics and is widely used worldwide for its medicinal and antioxidant benefits. This study aimed to investigate the possible protective effects of A. paniculata aqueous extract against HgCl2-induced memory impairment, oxidative stress, and brain damage. Twenty-five adult Wistar rats were randomly divided into five groups: control, HgCl2 0.5 mg/kg, HgCl2+AP 250 mg/kg, HgCl2+AP 500 mg/kg, or HgCl2+Ascorbic acid 200 mg/kg. For 28 days, administrations were given through oral gavage once a day. HgCl2 injection resulted in memory impairment, increased glutamate concentrations in the brain, and the production of oxidative stress. Memory impairment was prevented in A. paniculata-treated groups by balancing the levels of AChE and dopamine activities, which then lowered glutamate concentration, avoided oxidative stress, and improved histopathological alterations in the brain. A. paniculata alleviated HgCl2-induced memory impairment in Wistar rats by increasing the memory index, regulating neurotransmitter levels, and reducing oxidative stress.

Comprehensive Review Regarding Mercury Poisoning and Its Complex Involvement in Alzheimer's Disease

Mercury (Hg) is considered one of the most widespread toxic environmental pollutants, which seems to have multiple effects on organisms even at low concentrations. It has a critical role in many health problems with harmful consequences, with Hg primarily targeting the brain and its components, such as the central nervous system (CNS). Hg exposure was associated with numerous CNS disorders that frequently trigger Alzheimer's disease (AD). Patients with AD have higher concentrations of Hg in blood and brain tissue. This paper aims to emphasize a correlation between Hg and AD based on the known literature in the occupational field. The outcome shows that all these concerning elements could get attributed to Hg. However, recent studies did not investigate the molecular level of Hg exposure in AD. The present review highlights the interactions between Hg and AD in neuronal degenerations, apoptosis, autophagy, oxidative stress (OS), mitochondrial malfunctions, gastrointestinal (GI) microflora, infertility and altering gene expression.

Exploring Molecular Approaches in Amyotrophic Lateral Sclerosis: Drug Targets from Clinical and Pre-Clinical Findings

Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease (MND) characterized by the death of upper and lower motor neurons (corticospinal tract) in the motor cortex, basal ganglia, brain stem, and spinal cord. The patient experiences the sign and symptoms between 55 to 75 years of age, which include impaired motor movement, difficulty in speaking and swallowing, grip loss, muscle atrophy, spasticity, and sometimes associated with memory and cognitive impairments. Median survival is 3 to 5 years after diagnosis and 5 to 10% of the patients live for more than 10 years. The limited intervention of pharmacologically active compounds, that are used clinically, is majorly associated with the narrow therapeutic index. Pre-clinically established experimental models, where neurotoxin methyl mercury mimics the ALS like behavioural and neurochemical alterations in rodents associated with neuronal mitochondrial dysfunctions and downregulation of adenyl cyclase mediated cAMP/CREB, is the main pathological hallmark for the progression of ALS in central as well in the peripheral nervous system. Despite the considerable investigation into neuroprotection, it still constrains treatment choices to strong care and organization of ALS complications. Therefore, this current review specially targeted the investigation of clinical and pre-clinical features available for ALS to understand the pathogenic mechanisms and to explore the pharmacological interventions associated with the up-regulation of intracellular adenyl cyclase/cAMP/ CREB and activation of mitochondrial-ETC coenzyme-Q10 as a future drug target in the amelioration of ALS mediated motor neuronal dysfunctions.

Phytobiological-facilitated Production of Silver Nanoparticles From Selected Non-cultivated Vegetables in Nigeria and Their Biological Potential

Objectives

Plant-mediated synthesis [silver (Ag) to form Ag nanoparticles (AgNPs)] is becoming progressively well accepted in many scientific and pharmaceutical fields. The aim of this study was to synthesize AgNPs using air-dried leaves of four neglected vegetables, i.e. Ceratotheca sesamoides, Ceiba pentandra, Crassocephalum crepidioides, and Launaea taraxacifolia.

Materials and Methods

Ultraviolet-visible (UV-Vis) spectroscopy, fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) were used for characterization. Cell stabilization membrane and lipoxidase assays were used to determine used to assess the antiinflammatory activities while 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+) assays were used to assess the antioxidant activities of AgNPs [L. taraxacifolia-AgNPs, C. sesamoides Ag nanoparticles (CS-AgNPs), C. pentandra Ag nanoparticles (CP-AgNPs), and C. crepidioides AgNPs (CC-AgNPs)].

Results

The UV-Vis spectra of the synthesized NPs displayed absorption bands at around 360-440 nm, which is a characteristic band for AgNPs. The SEM image showed that the AgNPs formed were spherical in morphology. CC-AgNPs exhibited the most significant inhibitory activity against human red blood cell membrane stabilizasyonu [median inhibitory concentration (IC₅₀): 32.2 μg/mL] while CS-AgNPs displayed the most significant inhibitory activity against lipoxygenases (IC₅₀: 32.8 μg/mL). CP-AgNPs exhibited the most significant antioxidant effect against both ABTS and DPPH (IC₅₀: 5.5 and 6.4 μg/mL) when compared to ascorbic acid (IC₅₀: 4.7 μg/mL).

Conclusion

The synthesized AgNPs were found to be stable and the FTIR evidence suggested that the phytochemicals in the vegetables might have played an important role in the reduction and stabilization of AgNPs. This work showed that the synthesized AgNPs from non-cultivated vegetables can find relevance and application in health, drugs, food and environmental science. The evidences herein further confirmed their ethnopharmacological applications.

Composition of the Essential Oil and Insecticidal Activity of Launaea taraxacifolia (Willd.) Amin ex C. Jeffrey Growing in Nigeria

The rice weevil (Sitophilus oryzae) is a pest of stored grain products such as rice, wheat, and corn. Essential oils represent a green environmentally-friendly alternative to synthetic pesticides for controlling stored-product insect pests. Launaea taraxacifolia is a leafy vegetable plant found in several parts of Nigeria. The leaves are eaten either fresh as a salad or cooked as a sauce. The essential oil obtained from fresh leaves of L. taraxacifolia was obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC-MS). Twenty-nine compounds were identified, accounting for 100% of the oil composition. The major component classes were monoterpene hydrocarbons (78.1%), followed by oxygenated monoterpenoids (16.2%), sesquiterpene hydrocarbons (2.1%), oxygenated sesquiterpenoids (0.3%), and non-terpenoid derivatives (3.3%). The leaf essential oil was dominated by monoterpene hydrocarbons including limonene (48.8%), sabinene (18.8%), and (E)-β-ocimene (4.6%), along with the monoterpenoid aldehyde citronellal (11.0%). The contact insecticidal activity of L. taraxacifolia essential oil against Sitophilus oryzae was carried out; median lethal concentration (LC₅₀) values of topical exposure of L. taraxacifolia essential oil were assessed over a 120-h period. The LC₅₀ values ranged from 54.38 μL/mL (24 h) to 10.10 µL/mL (120 h). The insecticidal activity of the L. taraxacifolia essential oil can be attributed to major components limonene (48.8%), sabinene (18.8%), and citronellal (11.0%), as well as potential synergistic action of the essential oil components. This result showed L. taraxacifolia essential oil may be considered as a useful alternative to synthetic insecticides.

Toxicological Studies of Hydroethanolic Leaf Extract of Launaea taraxacifolia (Willd) Amin Ex C. Jeffrey on Wistar Rats

Launaea taraxacifolia (Asteraceae) is a widely used vegetable in West Africa. It is used in traditional healing of many diseases such as hypertension, anemia, diabetes, and bleeding. The aim of this study is to investigate the cytotoxicity and the acute and subacute (28 days) oral toxicity of L. taraxacifolia hydroethanolic leaves extract on male Wistar rats. The LC₅₀ values of L. taraxacifolia on brine shrimp were 0.142 ± 0.11 mg/mL. The limit test dose of 5000 mg/kg did not provoke death or toxicity signs in the rats tested during the observation period. For 28 days subacute toxicity at 500 and 1000 mg/kg body weight, no signs of toxicity or mortality were observed during the experiment. There was no significant difference between the treated groups and the control group concerning the body and the relative organs weight (P > .05). Results of biochemical and hematological parameters did not show any treatment-related abnormalities. According to our results, the hydroethanolic extract of L. taraxacifolia leaves, at 500 and 1000 mg/kg body weight, is safe when administrated to male Wistar rats for 28 days.

Medicinal plants and natural products can play a significant role in mitigation of mercury toxicity

Mercury is a heavy metal of considerable toxicity. Scientific literature reveals various plants and plant derived natural products, i.e., phytochemicals, which can alleviate experimentally induced mercury toxicity in animals. The present review attempts to collate those experimental studies on medicinal plants and phytochemicals with ameliorative effects on mercury toxicity. A literature survey was carried out by using Google, Scholar Google, Scopus and Pub-Med. Only the scientific journal articles found in the internet for the last two decades (1998–2018) were considered. Minerals and semi-synthetic or synthetic analogs of natural products were excluded. The literature survey revealed that in pre-clinical studies 27 medicinal plants and 27 natural products exhibited significant mitigation from mercury toxicity in experimental animals. Clinical investigations were not found in the literature. Admissible research in this area could lead to development of a potentially effective agent from the plant kingdom for clinical management of mercury toxicity in humans.

The Ethnopharmacological and Nutraceutical Relevance of Launaea taraxacifolia (Willd.) Amin ex C. Jeffrey

Launaea taraxacifolia (Willd.) Amin ex C. Jeffrey is a herb found mostly in tropical Africa. The plant, commonly found in West Africa, is used in the management of many diseases including cardiovascular, respiratory, haematological, endocrine, and metabolic diseases in Ghana, Nigeria, Benin, Serra Leone, and Senegal. This piece provides comprehensive and updated information on the traditional uses, phytochemical constituents, and pharmacological and toxicological information available on Launaea taraxacifolia to support its medicinal uses and also unearth knowledge gaps for future studies. An electronic literature search using search engines, namely, Google Scholar, ScienceDirect, and PubMed, was carried out to obtain information on the plant. Both common and scientific names of the plant were used as keywords for the search process. This paper captured information on Launaea taraxacifolia from 1985 to 2018. The search revealed that the leaves of the plant possess nutritional/pharmacological effects on diseases such as diabetes mellitus, hypertension, cancer, malaria, bacterial infections, and arthritis. The leaf has been shown to be a rich source of phytoconstituents such as flavonoids, phenolic acids, tannins, alkaloids, glycosides, coumarins, triterpenoids, ascorbic acid, lycopene, and β-carotene. Also, isolated phytoconstituents as well as the safety profile of the plant have been documented. This review on Launaea taraxacifolia has provided a one-stop documentation of information in support of the several purported ethnopharmacological uses of the plant. It also reveals information gaps such as the need to research into its pharmacokinetics, interactions with drugs of importance, and its development into a plant-based drug in order to expand its clinical use.