Attenuating effect of standardized fruit extract of Punica granatum L in rat model of tibial and sural nerve transection induced neuropathic pain

Solasodine Containing Solanum torvum L. Fruit Extract Prevents Chronic Constriction Injury-Induced Neuropathic Pain in Rats: In Silico and In Vivo Evidence of TRPV1 Receptor and Cytokine Inhibition

This study aimed to assess the efficacy of ethanolic extract of Solanum torvum L. fruit (EESTF) containing solasodine in treating chronic constriction injury (CCI)-induced neuropathic pain in rats. Three-dimensional (3D) simulation studies of solasodine binding were conducted on the TRPV1 receptor, IL-6, and TNF-α structures. For in vivo justification, an assessment of behavioral, biochemical, and histological changes was designed after a CCI-induced neuropathic pain model in rats. On days 7, 14, and 21, CCI significantly increased mechanical, thermal, and cold allodynia while producing a functional deficit. IL-6, TNF-α, TBARS, and MPO levels also increased. SOD levels of catalase and reduced glutathione levels also decreased. Administration of pregabalin (30 mg/kg, oral), solasodine (25 mg/kg, oral), and EESTF (100 and 300 mg/kg, oral) significantly reduced CCI-induced behavioral and biochemical changes (P < 0.05). The protective nature of EESTF was also confirmed by histological analysis. Capsaicin, a TRPV1 receptor agonist, abolished the antinociceptive effects of EESTF when used previously. From the observations of the docking studies, solasodine acted as an antagonist at TRPV1, whereas the docking scores of solasodine against TNF-α and IL-6 were reported to be -11.2 and -6.04 kcal/mol, respectively. The attenuating effect of EESTF might be related to its antagonistic effects on TRPV1, suppression of cytokines, and anti-inflammatory and antioxidant properties.

Preventive and Therapeutic Effects of Punica granatum L. Polyphenols in Neurological Conditions

Pomegranate (Punica granatum L.) is a polyphenol-rich food and medicinal plant containing flavonols, anthocyanins, and tannins. Ellagitannins (ETs) are the most abundant polyphenols in pomegranate. A growing body of research shows that polyphenol-rich pomegranate extracts and their metabolites target multiple types of brain cell and support their redox balance, proliferation and survival, as well as cell signaling. Independent studies have demonstrated that the significant neuroprotective effects of ETs are mediated by their antioxidant and anti-inflammatory effects, their chelating properties, by their ability to activate various signaling pathways, as well as the ability to influence mitochondrial damage, thus regulating autophagy, apoptosis and neurotransmitter signaling. The multitude of in vitro and in vivo studies summarized in the present review suggest that pomegranate polyphenols act on both neuronal and glial cells directly, and also affect blood-brain barrier function, restoring redox balance in the blood and brain and increasing blood flow to the brain.

Pharmacotherapeutic potential of pomegranate in age-related neurological disorders

Age-related neurological disorders [AND] include neurodegenerative diseases [NDDs] such as Alzheimer's disease [AD] and Parkinson's disease [PD], which are the most prevalent types of dementia in the elderly. It also includes other illnesses such as migraine and epilepsy. ANDs are multifactorial, but aging is their major risk factor. The most frequent and vital pathological features of AND are oxidative stress, inflammation, and accumulation of misfolded proteins. As AND brain damage is a significant public health burden and its incidence is increasing, much has been done to overcome it. Pomegranate (Punica granatum L.) is one of the polyphenol-rich fruits that is widely mentioned in medical folklore. Pomegranate is commonly used to treat common disorders such as diarrhea, abdominal pain, wound healing, bleeding, dysentery, acidosis, microbial infections, infectious and noninfectious respiratory diseases, and neurological disorders. In the current review article, we aimed to summarize the data on the pharmacotherapeutic potentials of pomegranate in ANDs.

The Impact of Supplements on Recovery After Peripheral Nerve Injury: A Review of the Literature

Peripheral nerve injury (PNI) can result from trauma, surgical resection, iatrogenic injury, and/or local anesthetic toxicity. Damage to peripheral nerves may result in debilitating weakness, numbness, paresthesia, pain, and/or autonomic instability. As PNI is associated with inflammation and nerve degeneration, means to mitigate this response could result in improved outcomes. Numerous nutrients have been investigated to prevent the negative sequelae of PNI. Alpha-lipoic acid, cytidine diphosphate-choline (CDP Choline), curcumin, melatonin, vitamin B12, and vitamin E have demonstrated notable success in improving recovery following PNI within animal models. While animal studies show ample evidence that various supplements may improve recovery after PNI, similar evidence in human patients is limited. The goal of this review is to analyze supplements that have been used successfully in animal models of PNI to serve as a reference for future studies on human patients. By analyzing supplements that have shown efficacy in animal studies, healthcare providers will have a resource from which to guide decision-making regarding future human studies investigating the role that supplements could play in PNI recovery. Ultimately, establishing a comprehensive understanding of these supplements in human patients following PNI may significantly improve post-surgical outcomes, quality of life, and peripheral nerve regeneration.

The Potential Benefits of Dietary Polyphenols for Peripheral Nerve Regeneration

Peripheral nerves are frequently affected by lesions caused by trauma (work accidents, car incidents, combat injuries) and following surgical procedures (for instance cancer resection), resulting in loss of motor and sensory function with lifelong impairments. Irrespective of the intrinsic capability of the peripheral nervous system for regeneration, spontaneous or surgically supported regeneration is often unsatisfactory with the limited functional success of nerve repair. For this reason, many efforts have been made to improve the regeneration process. Beyond innovative microsurgical methods that, in certain cases, are necessary to repair nerve injuries, different nonsurgical treatment approaches and adjunctive therapies have been investigated to enhance nerve regeneration. One possibility could be taking advantage of a healthy diet or lifestyle and their relation with proper body functions. Over the years, scientific evidence has been obtained on the benefits of the intake of polyphenols or polyphenol-rich foods in humans, highlighting the neuroprotective effects of these compounds in many neurodegenerative diseases. In order to improve the available knowledge about the potential beneficial role of polyphenols in the process of peripheral nerve regeneration, this review assessed the biological effects of polyphenol administration in supporting and promoting the regenerative process after peripheral nerve injury.

Alpha lipoic acid attenuated neuropathic pain induced by chronic constriction Injury of sciatic nerve in rats

Background

Chronic neuropathic pain syndrome is associated with impaired quality of life and is poorly manageable. Alpha lipoic acid (ALA) is a powerful antioxidant and showed its effectiveness on diabetic neuropathy and other acute peripheral nerve injuries but it was not evaluated in the chronic neuropathic pain, chronic constriction injury (CCI) in rat model by using duloxetine (DLX) as standard.

Methodology

The main objective of the study was to expedite ALA effect on chronic peripheral neuropathy induced by CCI of sciatic nerve in rats. In this study, male Wister rats were randomly divided into six groups (n = 8) including, normal saline, sham operated, surgery control, DLX 30mg/kg treated, ALA treated 25mg/kg, and ALA+DLX. The CCI of sciatic nerve was conducted on all animals except normal saline group and studied for 21 days (i.e. 14 days treatment period & 7 days treatment free period) by using different behavioral, biochemical and, histopathology studies.

Results

ALA showed minor but significant decrease of thermal hyperalgesia, cold allodynia, malondialdehyde (MDA), total protein, lipid peroxidation, and nitric oxide levels and significant increase of motor coordination, glutathione level and decreased axonal degeneration significantly. These effects sustained even during treatment free period. ALA enhanced the effect of DLX when given in combination by showing sustained effect. In conclusion, ALA acted as potent antioxidant may be this activity is responsible for the potent neuroprotective effect.

Conclusion

Hence, ALA attenuated the nueroinflammation mediated by chronic peripheral neuropathy. Further studies are warranted with ALA to develop as a clinically relevant therapeutic agent for the treatment of neuropathic pain.

Analgesic potency of intrathecally administered punicalagin in rat neuropathic and inflammatory pain models

Punicalagin, a natural polyphenolic compound classified as an ellagitannin, is a major ingredient of pomegranate (Punica granatum L.). Punicalagin has potent antioxidant and anti-inflammatory effects. Although the antinociceptive effects of orally administered pomegranate extracts have been reported, little is known about the effect of punicalagin on nociceptive transmission in the central nervous system. We examined whether punicalagin ameliorates neuropathic pain and inflammatory pain in the spinal cord. Male Sprague-Dawley rats were subjected to chronic constriction injury (CCI) of the sciatic nerve, and an intrathecal catheter was implanted for drug administration. The electronic von Frey test and cold-plate test were performed in CCI rats to evaluate mechanical and cold hyperalgesia in neuropathic pain, and the formalin test was performed in normal rats to evaluate acute and persistent inflammatory pain. An open-field test was conducted to explore whether punicalagin affects locomotor activity in CCI rats. Punicalagin administered intrathecally attenuated mechanical and cold hyperalgesia to the same degree as gabapentin in CCI rats and reduced pain-related behaviors in both the early and late phases in formalin-injected rats. Punicalagin did not affect motor function. These results suggest that punicalagin exerts an antinociceptive effect in the spinal cord without motor deficit, thus showing therapeutic potential for neuropathic pain and inflammatory pain.

Punicalagin and ellagic acid containing Punica granatum L. fruit rind extract prevents vincristine-induced neuropathic pain in rats: an in silico and in vivo evidence of GABAergic action and cytokine inhibition

Objectives: We aimed to investigate the protective potential of Punica granatum L. fruit rind extract (PFE) containing punicalagin (10.3% W/W), ellagic acid (EA) (2.7%W/W) in vincristine (75 µg/kg i.p.)- induced neuropathic pain in Wistar rats.Methods: Docking simulation studies were done on the three-dimensional (3D) structure of the GABA_A and PPAR γ receptor for the binding of EA as well as punicalagin docking studies on TNF-α, and IL-6. The Present Study conceptualized a test battery to evaluate the behavioral, biochemical and histological changes.Results: Vincristine -induced significant cold allodynia, mechanical hyperalgesia, and functional deficit on 12th and 21st days. It also increased in the levels of TNF-α (Tumor necrosis factor-α), IL-6 (Interleukin-6), and MPO (Myeloperoxidase). Administration of PFE (100 and 300 mg/kg, p.o.), EA (50 mg/kg), and gabapentin (100 mg/kg) attenuated Vincristine-induced behavioral and biochemical changes significantly (P < .05). PFE showed better antinociceptive activity to EA. The histopathological evaluation also revealed the protective effects of PFE. Pretreatment of bicuculline (selective antagonist of GABAA receptors) reversed antinociceptive action of PFE, but administration of γ aminobutyric acid potentiated the action of PFE. PPAR-γ antagonist BADGE did not modify the effect of PFE. Docking results revealed that EA properly positioned into GABA and PPARγ binding site and acts as a partial agonist. Docking score of Punicalagin found to be - 9.02 kcal/mol and - 8.32 kcal/mol on IL-6 and TNFα respectively.Discussion: Conclusively, the attenuating effect of PFE may be attributed to the GABAergic system, cytokine inhibition, and anti-inflammatory activities.

Punica granatum as a Source of Natural Antioxidant and Antimicrobial Agent: A Comprehensive Review on Related Investigations

BACKGROUND

The consumption of natural antioxidants is increasing due to the demand and tendency to natural foods. Punica granatum L. [Punicaceae] is a fruit with various bioactive ingredients. The effectiveness of this plant has been proved against various disorders such as hyperglycemia, hyperlipidemia, blood coagulation, infections, cancer, and dentistry. Among them, there are numerous researches on antimicrobial and antioxidant properties. Subsequently, the present study aimed to compile a review of those properties to outline this herb as a possible natural antioxidant and preservative.

METHODS

Synchronically, keywords "Punica granatum" with antimicrobial, or antibacterial, antifungal, antiviral, antioxidant and radical scavenging were searched through "Scopus" database up to 31st September 2019. Papers focusing on agriculture, genetics, chemistry, and environmental sciences were excluded, and also related papers were collected.

RESULTS

Among 201 papers focusing on related activities, 111 papers have dealt with antioxidant activities focusing based on DPPH assay, 59 with antibacterial, on both gram+ and gram- bacteria, 24 with antifungal effects, mostly on Aspergillus niger and Candida albicans, and 7 papers with antiviral activities. There were about 50 papers focusing on in-vivo antioxidant activities of this plant.

CONCLUSION

Taken together, botanical parts of P. granatum have possessed notable radical scavenging and antimicrobial activities that, with these properties, this plant can be introduced as a natural, safe source of preservative and antioxidant. Accordingly, P. granatum can be applied as excipient with the aforementioned properties in the pharmaceutical and food industries.

Pomegranate as a Potential Alternative of Pain Management: A Review

The use of complementary medicine has recently increased in an attempt to find effective alternative therapies that reduce the adverse effects of drugs. Punica granatum L. (pomegranate) has been used in traditional medicine for different kinds of pain. This review aims to explore the scientific evidence about the antinociceptive effect of pomegranate. A selection of original scientific articles that accomplished the inclusion criteria was carried out. It was found that different parts of pomegranate showed an antinociceptive effect; this effect can be due mainly by the presence of polyphenols, flavonoids, or fatty acids. It is suggested in the literature that the mechanisms of action may be related to the activation of the L-arginine / NO pathway, members of the TRP superfamily (TRPA1 or TRPV1) and the opioid system. The implications for the field are to know the mechanisms of action by which this effect is generated and thus be able to create alternative treatments for specific types of pain, which help alleviate it and reduce the adverse effects produced by drugs. The results propose that pomegranate and secondary metabolites could be considered in the treatment of inflammatory, nociceptive, and neuropathic pain.

Tumor necrosis factor alpha mediates orofacial discomfort in an occlusal dental interference model in rats: The role of trigeminal ganglion inflammation

BACKGROUND

Tumor necrosis factor alpha (TNF-α) is a proinflammatory cytokine that plays an important role in the early stages of inflammation. In this study, we investigated its role in orofacial discomfort in rats subjected to occlusal dental interference (ODI).

METHODS

Female Wistar rats (180-200 g) were divided in three groups (n = 30/group): sham group, without ODI, and two experimental groups with ODI pre-treated with 0.1 mL/kg saline (ODI + SAL) or 5 mg/kg infliximab (ODI + INF) and treated every 3 days. The animals were euthanized after 1, 3, and 7 days. The number of bites and scratches and grimace scale scores were determined daily, and the bilateral trigeminal ganglion was histomorphometrically (neuronal body area) analyzed and submitted for immunohistochemistry for TNF-α, nitric oxide synthesis (NOS) neuronal (nNOS) and inducible (iNOS), peroxisome proliferator-activated receptors (PPAR) y (PPARy) and δ/β (PPARδ/β), and glial fibrillary acidic protein (GFAP). One-way/two-way ANOVA/Bonferroni tests were used (P < .05, GraphPad Prism 5.0).

RESULTS

ODI + SAL showed a large number of bites (P = .002), scratches (P = .002), and grimace scores (P < .001) in the firsts days, and ODI + INF partially reduced these parameters. The contralateral and ipsilateral neuronal body area was significantly reduced on day 1 in ODI + SAL, but returned to the basal size on days 3 and 7, by increase in TNF-α, nNOS, PPARy, PPARδ/β, and GFAP immunostaining. The infliximab treatment attenuated these alterations (P < .05). There was no iNOS immunostaining.

CONCLUSION

Occlusal dental interference induced transitory orofacial discomfort by trigeminal inflammatory mediator overexpression, and TNF-α blockage attenuated these processes.

Plants mentioned in the Islamic Scriptures (Holy Qur'ân and Ahadith): Traditional uses and medicinal importance in contemporary times

ETHNOPHARMACOLOGICAL RELEVANCE

Over the past thousand years, Islamic physicians have collected cultural, philosophical, sociological and historical backgrounds for understanding diseases and medications. The Prophet Mohammed (Peace Be Upon Him (PBUH) said: "There is no disease that Allah has created, except that Allah also has created its cure." Therefore, Islamic scholars are encouraged to explore and use both traditional and modern forms of medicine.

AIM OF THE STUDY

(1) To identify some of the medicinal plants mentioned in the Holy Qur'ân and Ahadith textbooks of the period 700-1500 AD; (2) to compare them with presently used traditional medicines; (3) to evaluate their value based on modern research; and (4) to investigate the contributions of Islamic scholars to the development of the scientific branches, particularly medicine.

MATERIALS AND METHODS

A literature search was performed relating to 12 medicinal plants mentioned in the Holy Qur'ân and Ahadith using textbooks, Al-Azhar scholars, published articles, the plant list website (http://www.theplantlist.org/), the medicinal plant names services website (http://mpns.kew.org/mpns-portal/) and web databases (PubMed, Science Direct, and Google Scholar).

RESULTS AND DISCUSSION

The Islamic Golden Age was a step towards modern medicine, with unique insights and multi-disciplinary aspects. Traditional Islamic Medicine has had a significant impact on the development of various medical, scientific and educational activities. Innumerable Muslim and non-Muslim physicians have built on the strong foundation of Traditional Islamic Medicine by translating the described natural remedies and effects. The influences of different ancient cultures on the traditional uses of natural products were also documented in Islamic Scriptures in the last part of the second millennium. The divine teachings of Islam combine natural and practical healing and incorporate inherited science and technology.

CONCLUSION

In this review, we discuss Traditional Islamic Medicine with reference to both medical recommendations mentioned in the Holy Qur'ân and Prophetic Traditional Medicine (al-Tibb al-Nabawi). Although the molecular mechanisms and functions of some of the listed medicinal plants and their derivatives have been intensively studied, some traditional remedies have yet to be translated into clinical applications.

Distinct calcitonin gene-related peptide expression pattern in primary afferents contribute to different neuropathic symptoms following chronic constriction or crush injuries to the rat sciatic nerve

Although calcitonin gene-related peptide is a recognized pain transducer, the expression of calcitonin gene-related peptide in primary afferents may be differentially affected following different types of nerve injury. Here, we examined whether different calcitonin gene-related peptide expression patterns in primary afferents contributes to distinct sensory disturbances in three animal models of sciatic nerve injury: chronic constriction injury, mild (100g force) or strong (1000g force) transient crush in rats. Assessments of withdrawal reflexes and spontaneous behavior indicated that chronic constriction injury and mild crush resulted in positive neuropathic symptoms (static/dynamic mechanical allodynia, heat hyperalgesia, cold allodynia, spontaneous pain). However, strong crush led to both positive (dynamic mechanical allodynia, cold allodynia, spontaneous pain) and negative symptoms (static mechanical hypoesthesia, heat hypoalgesia). Calcitonin gene-related peptide immunoreactivity in dorsal root ganglia and corresponding spinal cord segments, and calcitonin gene-related peptide mRNA levels in dorsal root ganglia, indicated that the primary afferent calcitonin gene-related peptide supply was markedly reduced only after strong crush. This reduction paralleled the development of negative symptoms (static mechanical hypoesthesia and heat hypoalgesia). Administration of exogenous calcitonin gene-related peptide intrathecally after strong crush did not alter heat hypoalgesia but ameliorated static mechanical hypoesthesia, an effect blocked by a calcitonin gene-related peptide receptor antagonist. Thus, reducing the primary afferent calcitonin gene-related peptide supply contributed to subsequent negative neuropathic symptoms, especially to static mechanical stimuli. Moreover, nerve injury caused a subcellular redistribution of calcitonin gene-related peptide from small- and medium-size dorsal root ganglia neurons to large-size dorsal root ganglia neurons, which paralleled the development of positive neuropathic symptoms. Intrathecal administration of the calcitonin gene-related peptide receptor antagonist ameliorated these positive symptoms, indicating that the expression of calcitonin gene-related peptide in large-size dorsal root ganglia neurons is important for the positive neuropathic symptoms in all three models. Taken together, these results suggest that distinct calcitonin gene-related peptide expression pattern in primary afferents contribute to different neuropathic symptoms following chronic constriction or crush injuries to the rat sciatic nerve.

Ellagic acid protects against neuron damage in ischemic stroke through regulating the ratio of Bcl-2/Bax expression

An oxygen-glucose deprivation and reoxygenation model in primary cultured rat cortical neurons was developed for this study to investigate the effects of ellagic acid (EA), a low-molecular-weight polyphenol, on neuron cells and their function, and to evaluate whether EA can be safely utilized by humans as a functional food or therapeutic agent. Administration of EA significantly decreased the volume of cerebrum infarction and the neurological deficit scores of the rats; EA treatment also increased the number of Bcl-2-positive cells and the ratio of Bcl-2-positive to Bax-positive neurons in the semidarkness zone near the brain ischemic focus in the photothrombotic cerebral ischemia model. Treatment of EA resulted in increased neuron viability, cell nuclear integrity, and the ratio of Bcl-2/Bax expression in the primary cultured neuron model; EA treatment also lead to a decrease in the number of apoptotic cells. Our results therefore suggest a specific mechanism for the beneficial effects of EA, providing new insights into how it provides neuroprotection. To the best of our knowledge, these results represent new insights on the mechanisms of the brain cell protective activity of EA. Thus, EA may be used in functional foods or medicines to help treat nerve dysfunction, neurodegenerative disease, and aging.

Anti-inflammatory potential of ellagic acid, gallic acid and punicalagin A&B isolated from Punica granatum

Background

Punica granatum (pomegranate), an edible fruit originating in the Middle East, has been used as a traditional medicine for treatment of pain and inflammatory conditions such as peptic ulcer. The numerous risks associated with nonsteroidal anti-inflammatory drugs (NSAIDs) for treatment of pain and inflammation give rise to using medicinal herbs as alternative therapies. This study aimed to evaluate the anti-inflammatory effect of isolated compounds from the ethyl acetate (EtOAc) fraction of P. granatum by determination of their inhibitory effects on lipopolysaccharide (LPS), stimulated nitric oxide (NO), prostaglandin E2 (PGE-2), interleukin-6 (IL-6) and cyclooxxgenase-2 (COX-2) release from RAW264.7 cells.

Methods

The compounds ellagic acid, gallic acid and punicalagin A&B were isolated from EtOAc by high performance liquid chromatography (HPLC) and further identified by mass spectrometry (MS). The inhibitory effect of ellagic acid, gallic acid and punicalagin A&B were evaluated on the production of LPS-induced NO by Griess reagent, PGE-2 and IL-6 by immunoassay kit and prostaglandin E2 competitive ELISA kit, and COX-2 by Western blotting.

Results

Ellagic acid, gallic acid and punicalagin A&B potentially inhibited LPS-induced NO, PGE-2 and IL-6 production.

Conclusion

The results indicate that ellagic acid, gallic acid and punicalagin may be the compounds responsible for the anti-inflammatory potential of P. granatum.

Efficacy of the Punica granatum peels aqueous extract for symptom management in ulcerative colitis patients. A randomized, placebo-controlled, clinical trial

OBJECTIVE

To investigate the effects of the Punica granatum peel extract on symptoms of patients with ulcerative colitis (UC).

METHOD

Patients with UC were randomized to receive an aqueous extract of the P. granatum peel (6 g of dry peel/day) or placebo for four weeks complementary to standard medications. Symptoms were assessed using the Lichtiger Colitis Activity Index (LCAI) at baseline, week 4, and week 10 (follow-up). Clinical response was defined by ≥ 3 point decrease in LCAI.

RESULTS

The LCAI score was similarly reduced in both the P. granatum (-1.68 ± 3.85, P = 0.019) and placebo groups (-1.39 ± 2.41, P = 0.002). Clinical response was higher with P. granatum compared with placebo at week 4 (41.4% vs. 18.2%, P = 0.055), but not at week 10 (48.3% vs. 36.4%, P = 0.441).

CONCLUSIONS

The P. granatum peel extract seems effective in complementary management of UC. Further studies in a larger sample of patients are warranted. IRCT2014040617156N1.