Neurodegenerative diseases (ND) are threatening worldwide. Epidemiological studies obviously represent substantial burden on well-being. Previously countless medications are obtainable for ND, but all the drugs are symptomatic relief only and they do not ameliorate the total mechanism of illnesses. ND was traditionally treated with numerous herbal medicines because to minimize side and adverse effects, chemical pollution from synthetic medications. Publics are accepting the herbal medicines due to long history of usage, better patient tolerance, easy availability, cost
effective, time consuming.
Huge number of behavioural changes are associated with ND such as depression, anxiety, memory loss, stress and so on. It affects not only adult, even small kids also suffering a lot due to depression and stress. Effective drugs need to cure the ND from nature. Now a day, people are focused on an organic product from herbal plants.
In this present study, we had evaluated the phytochemical characterization and neuroprotective assessment of standardized extract (90% v/v Ethanol) of Pedalium murex Linn. leaves against LPS-induced endotoxemia in SD rats. Previously many work had been done on this plant except LPS-induced neurodegeneration along with behavioural and biochemical alterations.
Preliminary phytochemical studies in Pedalium murex Linn. leaves confirm the presence of flavonoids, triterpenoids, steroids, tannins, phenolic compounds in four different extracts such as n-Hexane extract, Chloroform extract, Ethyl acetate extract, 90% v/v of Ethanol extract.
In vitro free radical scavenging activity proved that, the 90% v/v of ethanol extract of Pedalium murex Linn. leaves (EEPM) were significantly acts against the free radicals. IC50 values were represents, EEPM possessed strong antioxidant activity when compared to n-hexane extract, chloroform extract, ethyl acetate extract of Pedalium murex Linn. leaves.
From the results of preliminary phytochemical and in vitro free radical scavenging studies, EEPM was selected for phytochemical characterization and neuroprotective assessment.
TLC study has been performed on pre-coated silica gel plates for elution. Based on trial and error method, 5:4:1 ratio of Toluene: Ethyl acetate: Formic acid were used as a mobile phase, iodine vapors used as detecting agent. Six spots were observed. From the TLC study, isolation of active constituents of EEPM was done by column chromatography (CC) through isocratic elution technique with the help of same solvent system. Two compounds were isolated from CC fractions, 25-28, 33-36 and named as PM I, PM II. These two compounds were subjected to physical, chemical and spectral studies to authorizing the purity and characterization of isolated compounds of EEPM.
Spectral data of isolated compounds strongly suggested that PM I showed the structural similarities with 4´, 5, 7- trihydroxy flavone may be Apigenin and PM II showed the structural similarities with 3,5,7-Trihydroxy-2-(4-hydroxyphenyl)-4Hchromen-4-one which may have the presence of kaempferol. PM I and PM II may be a flavonoids type of compounds.
HPTLC fingerprint profile of flavonoids and steroids showed that more number of flavonoids and steroidal compounds were present in EEPM. Quantitative estimation also recommended the presence of flavonoids and phenolic compounds in EEPM.
EEPM was subjected to animal studies. Acute toxicity studies revealed up to 2000 mg/kg dose of EEPM did not show any toxic signs in animals. The present study proved that endotoxin (LPS) administration reduces the social, exploratory and locomotor activity which was leads the depression, anxiety, cognition impairment such as long-term memory, short-term memory, attention capacity of the animal. LPS completely degenerate the CA1 hippocampal region of the brain.
The data of our present study revealed that LPS significantly decreases the food, water intake and body mass which was recovered EEPM treated rats. In open field test, reduced level of animal’s locomotion indicates that the depression and anxiety level was significantly more in LPS-induced rats. EEPM 400 mg/kg significantly increases the movement of animal through diminish the depression. Elevated plus maze test showed repeated animal entries in closed arms represents the immune activation and depression was produced by LPS, which was significantly antagonized by EEPM in different doses.
Immobility time was increased in LPS-treated rats in forced swim test, hence EEPM treated rats were anticipated to recover from depression. Moreover, treatment with EEPM different doses attenuated or completely abolished these symptoms of depression and anxiety.
EEPM provides excellent activity against cognitive impairment, increases the learning and memory power of the animals. LPS-treated rats attained long-term memory loss that’s why the swimming length was increased due to confusion to reach circular platform of water maze apparatus & EEPM 400 mg/kg significantly recover the memory power of animals. Short-term memory power loss and minimum number of rewards (food pellets) induced by LPS in radial arm maze test. EEPM 400 mg/kg increases the maximum no of rewards and minimum number of errors and enhance the learning, memory power of the animals. Attention capacity was measured in choice reaction time task test. Incorrect lever pressing for reward (food pellets) was increased in LPS-treated rats recovered by EEPM 400 mg/kg.
Antioxidant enzymes includes SOD, CAT, GR, GPX levels were decreased in LPS-treated rats. An increased level of these antioxidant enzymes was observed after administration of EEPM, which indicates the antioxidant activity. ACh level was decreased and AChE level was increased in LPS-treated rats due to beta amyloid precursor protein degeneration which was reversed by EEPM treated rats. An increased level of nitric oxide and lipid per-oxidation (LPO) and decreased level of protein in LPS-treated rats was antagonized by various doses of EEPM. Histopathological results also support the neuroprotective effect of EEPM against LPS-induced neurodegeneration.
From the above results, we may conclude that EEPM may be a potential candidate for LPS-induced brain damage which may be attributed to the presence of potent antioxidants in EEPM. The results of this study warranted further research on active constituents of EEPM through molecular docking will lead new therapeutic approaches from nature
