Carica papaya(Paw-Paw) Unripe Fruit May Be Beneficial in Ulcer

Changes in gut microbiota linked to a prevention of cardiac remodeling induced by hypertension in spontaneously hypertensive rats fed a pawpaw fruit diet

Objective

Dietary intake of fruit is associated with lower incidence of hypertension and cardiovascular risk. Papaya is a kind of delicious fruit and reported has dietary therapeutic effects, such as digestive stimulation and hypotensive efficacy. However, the mechanism of pawpaw involved have not been elucidated. Here, we illustrate that the effect of pawpaw on the gut microbiota and the prevention of cardiac remodeling.

Methods

Gut microbiome, cardiac structure/function, and blood pressure were examined in SHR and WKY groups. The intestinal barrier was tested with histopathologic; immunostaining and Western blot were used to measure the tight junction protein level; Gpr41 was tested by RT-PCR, and inflammatory factors were detected with ELISA.

Results

We observed a significant decrease in microbial richness, diversity, and evenness is the spontaneously hypertensive rat (SHR), in addition to an increased Firmicutes/Bacteroidetes (F/B) ratio. These changes were accompanied by decreased in acetate and butyrate-producing bacteria. Compared with SHR, treatment with pawpaw at the dosage of 10 g/kg for 12 weeks significantly reduced the blood pressure, cardiac fibrosis and cardiac hypertrophy, while the ratio of F/B decreased. We also found that the concentration of short-chain fatty acids (SCFAs) was increased in SHR fed with pawpaw compared with that in control group, while the gut barrier was restored and level of proinflammatory cytokines in the serum were decreased.

Conclusions

Pawpaw, rich of high fiber, led to changes in the gut microbiota that played a protective role in the development of cardiac remodeling. The potential mechanism of pawpaw may explained by the generation of one of the main metabolites of the gut microbiota, the short-chain fatty acid acetate, increasing tight junction protein level occluding to enhance the gut barrier for less releasing the inflammation cytokines, and upregulating G-protein-coupled receptor 41 (GPR41) to reduce blood pressure.

An insight into the anti-ulcerogenic potentials of medicinal herbs and their bioactive metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

Peptic ulcer disease (PUD) ranks top among the most prominent gastrointestinal problems prevalent around the world. Long-term use of non-steroidal anti-inflammatory drugs, pathogenic infection by Helicobacter pylori, imbalances between gastrointestinal regulatory factors and pathological hyperacidity are major contributors towards the development of peptic ulcers. Although synthetic drugs of multiple pharmacological classes are abundantly available, inadequacy of such agents in ensuring complete recovery in not uncommon. Therefore, pharmacological explorations of herbal products including plant extracts and their respective isolated phytoconstituents, for potential gastroprotective and antiulcer properties, are regular practice among the scientific community. Moreover, the historical preferences of a significant share of world population towards herbal-based medication over modern synthetic drugs also contribute significantly to such endeavors.

AIM OF THE REVIEW

This review has endeavored to present ethnomedicinal and pharmacological prospects of a significant number of authenticated plant species in terms of their capacity to exert gastroprotection and antiulcer activities both in vitro and in vivo. The information delineated along the way was further subjected to critical analysis to ascertain the possible future prospects of such findings into designing plant-derived products in future for the treatment of peptic ulcer.

MATERIALS AND METHODS

Electronic version of prominent bibliographic databases, including Google Scholar, PubMed, Scopus, ScienceDirect, Wiley Online Library, SpringerLink, Web of Science, and MEDLINE were explored extensively for the identification and compilation of relevant information. The plant names and respective family names were verified through the Plant List (version 1.1) and World Flora Online 2021. All relevant chemical structures were verified through PubChem and SciFinder databases and illustrated with ChemDraw Ultra 12.0.

RESULTS

A colossal number of 97 plant species categorized under 58 diverse plant families have been discussed in the review for their gastroprotective and antiulcer properties. In vivo illustrations of the pharmacological properties were achieved for almost all the species under consideration. 29 individual phytoconstituents from these sources were also characterized with similar pharmacological potentials. Majority of the plant extracts as well as their constituents were found to exert their gastroprotective effects through antioxidative pathway featuring both enzymatic and nonenzymatic mechanism. Moreover, active inhibition of acid secretion, upregulation of gastroprotective mediators and downregulation of pro-inflammatory cytokines, were also associated with a prominent number of plants or products thereof.

CONCLUSIONS

Comparative evaluations of the plant sources for their antiulcer activities, both as individual and as combination formulations, are necessary to be conducted in human subjects under properly regulated clinical conditions. Moreover, the efficacy and safety of such products should also be evaluated against those of the currently available treatment options. This will further facilitate in ascertaining their suitability and superiority, if any, in the treatment of peptic ulcer diseases. Implementation of these endeavors may eventually lead to development of more efficient treatment options in the future.

Region-specific effects of the cysteine protease papain on gastric motility

BACKGROUND

Papaya is a traditional remedy for gastrointestinal complaints in the folk medicine. On this basis, papain, a cysteine protease of the fruit, is sold as a nutritional supplement, although scientific data on its effects in the gastrointestinal tract are lacking. We aimed to explore the effect of papain on gastric motility in vitro.

METHODS

Guinea pig antrum and corpus strips were mounted in organ bath.

KEY RESULTS

Papain reversibly increased the amplitude of ongoing phasic contractions in both circular and longitudinal antrum strips without having an effect on the frequency or on the muscle tone. All three tested doses of papain (end cc.: 12.5 mg L^-1 , 50 mg L^-1 , 100 mg L^-1 ) were similarly effective. Contrarily, in the corpus circular and longitudinal muscle strips, papain caused a dose-dependent relaxation, which was preceded by a transient contraction in most tissues. The effect was resistant to tetrodotoxin (1 µM), but diminished by the cysteine protease inhibitor E64 (4.5 µM) in both regions. In the corpus, L-NAME (100 µM) and the protease-activated receptor (PAR)-1 antagonist SCH79797 (5 µM) or the PAR-2 antagonist GB 83 (3 µM) did not change the effect of papain significantly. This demonstrates that the effects of papain are not neurally mediated and nitrergic pathways are not involved in the mechanism. The effects are linked to the enzymatic activity, but not executed via PAR-1 or 2.

CONCLUSIONS AND INFERENCES

Papain alters gastric motility in a region-specific manner, which could at least partly explain its claimed beneficial effects in functional gastrointestinal disorders.

Potential Antiulcer Agents From Plants: A Comprehensive Review

Background:

Peptic ulcer is a deep gastrointestinal erosion disorder that involves the entire mucosal thickness and can even penetrate the muscular mucosa. Nowadays, several plants and compounds derived from it have been screened for their antiulcer activity. In the last few years, there has been an exponential growth in the field of herbal medicine. This field has gained popularity in both developing and developed countries because of their natural origin and less side effects.

Objective:

This review aims to provide a comprehensive summary of currently available knowledge of medicinal plants and phytoconstituents reported for their anti-ulcer properties.

Methods:

The worldwide accepted database like SCOPUS, PUBMED, SCIELO, NISCAIR, ScienceDirect, Springerlink, Web of Science, Wiley, SciFinder and Google Scholar were used to retrieve available published literature.

Results:

A comprehensive review of the present paper is an attempt to list the plants with antiulcer activity. The review narrates the dire need to explore potential chemical moieties that exert an antiulcer effect, from unexploited traditional plants. Furthermore, the present study reveals the intense requirement to exploit the exact mechanism through which either the plant extracts or their active constituents exhibit their antiulcer properties.

Conclusion:

This article is the compilation of the plants and its constituents reported for the treatment of peptic ulcers. The Comprehensive data will surely attract the number of investigators to initiate further research that might lead to the drugs for the treatment of ulcers. As sufficient scientific data is not available on plants, most of the herbals cannot be recommended for the treatment of diseases. This can be achieved by research on pure chemical structures derived from plants or to prepare new lead compounds with proven beneficial preclinical in vitro and in vivo effects. However, a lot remains to be done in further investigations for the better status of medicinal plants.

Novel and classical renal biomarkers as evidence for the nephroprotective effect of Carica papaya leaf extract

The present study is aimed at utilization of novel and classical kidney function biomarkers to evaluate the nephroprotective potential of Carica papaya leaf extract (CPLE) in gentamicin nephrotoxicity model in albino rats. The used classical biomarkers were urea and creatinine; while the new biomarkers were Kidney injury molecule-1 (KIM-1) and Clusterin. Forty-five male albino rats were assigned into five groups and subjected to different treatments for nine consecutive days (vehicles; gentamicin, 100 mg/kg, subcutaneously; ascorbic acid, 200 mg/kg, orally; CPLE, 150 and 300 mg/kg b wt., orally). Three rats/group were killed on days 3, 6, and 9 for blood and tissue samples for renal and oxidation markers. Gentamicin resulted in significant increase in urea and creatinine only by the end of the experimental course; while the novel biomarkers were evident as early as 3 days upon gentamicin injection. When concurrently administered with gentamicin, CPLE significantly protected kidney tissues against gentamicin nephrotoxic effects indicated by decrement of both the novel and the classical standard biomarkers, in a dose-dependent manner. CPLE-mediated protection was attributed to its antioxidant potential indicated by significant inhibition of malondialdehyde (MDA) levels in both serum and kidney homogenates. The results were further supported by histopathological examination that revealed considerable amelioration of the pathological microscopic alterations induced by repeated gentamicin injection. Phytochemical analysis of CPLE indicated presence of tannins and flavonoids. These data may suggest CPLE, based on improvement of both classical and novel renal markers, as a highly potent nephroprotective and antioxidant from natural source that could be a good remedy in conditions associated with renal disorders.

Antiulcer properties of fruits and vegetables: A mechanism based perspective

Gastric ulcer is the damage caused to mucosal layer of the stomach under the action of various factors like high levels of acid and pepsin, invasion by Helicobacter pylori, etc. Although most cases have been controlled and the rate of ulcer occurrence has reduced over the last few decades, gastric ulcer still holds a prime concern today. A range of palliative medicines comprising proton pump inhibitors, H2 receptor antagonists, COX-2 inhibitors (coxibs) is widely in use and patients have also been administered with acid suppression therapies. But these remedies aggravate the condition of patients causing severe side effects, or rather impart temporary relief. Therefore, it is highly imperative to develop safe and effective therapies for the treatment of gastric ulcer. Nature provides us various fruits and vegetables that can combat gastric ulcer through multiple mechanisms; predominantly via antioxidant, anti-inflammatory, antisecretory, antimicrobial, anticholinergic and cytoprotective activity, inhibition of small intestinal propulsion etc. Various phytochemicals from fruits and vegetables such as phenolics, flavonoids, tannins and saponins play a vital role in the prevention and cure of gastric ulcer. This review is a compendium of all fruits and vegetables known for their profound antiulcer effect and their underlying mechanisms of action.

Selective anti-proliferative activities of Carica papaya leaf juice extracts against prostate cancer

BACKGROUND

Prostate cancer (PCa) is the leading cause of cancer related deaths in men. Carica papaya is a popular tropical plant that has been traditionally used for its nutritional and medicinal properties.

METHODS

We investigated the anti-proliferative responses of papaya leaf juice (LJP) and its various extracts ("biological"- in vitro digested, "physical"- size exclusion, and "chemical"-solvent extraction) on a range of cell lines representing benign hyperplasia, tumorigenic and normal cells of prostate origin.

RESULTS

Time course analysis (by 24h, 48h and 72h) of LJP (1-0.1mg/mL) before and after in vitro digestion, and of molecular weight based fractions of LJP showed anti-proliferative responses. The medium polarity fraction of LJP (0.03-0.003mg/mL) after 72h exposure showed potent growth inhibitory (IC₅₀=0.02-0.07mg/mL) and cytotoxic activities on all prostate cells, with the exception of the normal (RWPE-1 and WPMY-1) cells. Flow cytometry analysis showed S phase cell cycle arrest and apoptosis as a possible mechanism for these activities. Medium polar fraction of LJP also inhibited migration and adhesion of metastatic PC-3 cells.

CONCLUSION

This is the first report suggesting selective anti-proliferative and anti-metastatic attributes of LJP extract against prostatic diseases, including PCa.

Carica papaya induces in vitro thrombopoietic cytokines secretion by mesenchymal stem cells and haematopoietic cells

Background

Use of Carica papaya leaf extracts, reported to improve thrombocyte counts in dengue patients, demands further analysis on the underlying mechanism of its thrombopoietic cytokines induction

Methods

In vitro cultures of peripheral blood leukocytes (PBL) and stem cells from human exfoliated deciduous teeth (SHED) were treated with unripe papaya pulp juice (UPJ) to evaluate its potential to induce thrombopoietic cytokines (IL-6 and SCF)

Results

In vitro scratch gap closure was significantly faster (p < .05) in SHED culture treated with UPJ. IL-6 concentration was significantly increased (p < .05) in SHED and PBL culture supernatant when treated with UPJ. SCF synthesis in SHED culture was also significantly increased (p < .05) when treated with UPJ

Conclusion

In vitro upregulated synthesis of IL −6 and SCF both in PBL and SHED reveals the potential mechanism of unripe papaya to induce thrombopoietic cytokines synthesis in cells of hematopoietic and mesenchymal origin.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-015-0749-6) contains supplementary material, which is available to authorized users.

The component of Carica papaya seed toxic to A. aegypti and the identification of tegupain, the enzyme that generates it

As Aedes aegypti transmits the etiologic agents of both yellow and dengue fever; vector control is considered essential to minimise their incidence. The aim of this work was to identify the component of Carica papaya seed toxic to A. aegypti, and the identification of tegupain, the enzyme that generates it. Aqueous extracts (1%, w/v) of the seed tegument and cotyledon of C. papaya are not larvicidal isolately. However, a mixture of 17μgmL(-1) tegument extract and 27μgmL(-1) cotyledon extract caused 100% larval mortality in a bioassay. The mixture was no longer larvicidal after the tegument extract was pre-treated at 100°C for 10min. The enzyme tegupain efficiently hydrolysed the substrate Z-Phe-Arg-pNan (Km 58.8μM, Kcat 28020s(-1), Kcat/Km 5×10(8)M(-1) s(-1)), and its activity increased with 2mM dithiothreitol (DTT), at 37°C, pH 5.0. The chelating agent EDTA did not modify the enzyme activity. Inhibition of tegupain by cystatin (Kiapp 2.43nM), E64 (3.64nM, 83% inhibition), and the propeptide N-terminal sequence indicate that the toxic activity is due to a novel cysteine proteinase-like enzyme, rendered active upon the hydrolysis of a cotyledon component of C. papaya seeds.

Ethnopharmacological survey of medicinal plants used by traditional healers in Bangladesh for gastrointestinal disorders

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrointestinal diseases are common worldwide, including Bangladesh where majority of the rural people depend on water from unprotected sources. The people from Bangladesh use medicinal plants as their first line of health care to cure and prevent different types of gastrointestinal disorders.

AIM OF THE STUDY

To compile plants used for the treatment of different gastrointestinal disorders in Bangladesh.

MATERIALS AND METHODS

The field survey was carried out in a period of 18 months. Fieldwork was undertaken in total of eleven districts of Bangladesh. Open-ended and semi structured questionnaire were used to interview a total of 1280 people including traditional healers, Ayurvedic/Unani drug manufacturers and local people.

RESULTS

A total of 250 plant species of 93 families were listed. Leaves were the most cited plant part used against gastrointestinal disorders. Most of the reported species were tree in nature and decoction is the mode of preparation of major portions of the plant species. Most of the plant species were very common and were cultivated or planted in homestead or roadsides. The doses of the plants for different treatments varied widely.

CONCLUSION

In view of the fact that the plants were selected based on their medicinal usage for treating different kinds of gastrointestinal diseases including diarrhoea, the activities reported here need more works for validation and could be rationalised by the presence of active compounds found in those plants. The documentation represents the preliminary information in need of future phytochemical investigation and is important for the conservation of these plants.

Effect of Flabellaria paniculata Cav. extracts on gastric ulcer in rats

Background

The leaves and root of Flabellaria paniculata (Malpighiaceae) are frequently used in the treatment of wounds and ulcers in Nigerian folk medicine. The purpose of this study was to compare the effect of ethanolic extracts from the leaves (FPL) and root (FPR) of F. paniculata on gastric ulcers in rats.

Methods

The effect of FPL and FPR (100, 200 and 400 mg/kg) was evaluated in ethanol and indomethacin gastric ulcer models. Control groups for FPL and FPR were orally treated with 3% Tween 20 and distilled water respectively. FPL was further investigated in pylorus ligation model. Misoprostol and cimetidine were used as reference.

Results

FPL significantly (P < 0.05) reduced gastric lesions by 82.22% and 67.32% in ethanol and indomethacin induced ulcer models at 100 mg/kg respectively while FPR (100, 200 and 400 mg/kg) did not exert significant effect in the two models. In pylorus ligation model, FPL exerted a significant preventive antiulcer effect as indicated by reduction in gastric volume at 200 and 400 mg/kg doses. Only 400 mg/kg of the extract exerted a significant reduction in ulcer index when compared with the control group. The oral route LD₅₀ of FPL was estimated to be 4570 mg/kg while that of FPR was 2754 mg/kg. The LD₅₀ in intraperitoneal injection was estimated to be 1202.26 and 1380.38 mg/kg for FPL and FPR respectively. The phytochemical investigation showed that both extracts possess triterpenoids and saponin, while the presence of flavonoid was detected only in FPL.

Conclusions

The results of this study indicated that FPL and not FPR is effective against experimentally induced gastric ulcers. The presence of varied phytochemical constituents probably influenced the pharmacological differences between the two extracts.

Ethnobotanical survey of Purulia district, West Bengal, India for medicinal plants used against gastrointestinal disorders

ETHNOPHARMACOLOGICAL RELEVANCE

An ethnobotanical survey was conducted in the remote hills, forests and rural areas of Purulia, one of the tribal rich districts of the West Bengal state of eastern India. Purulia is a part of the biogeographic zone Deccan Peninsula Chhotonagpur. The authors have reported the use of medicinal plants by nine tribes of the district against various gastrointestinal disorders.

MATERIALS AND METHODS

Semi structured questionnaire was used during the interview with the informants having traditional botanical knowledge. Bhumijs, Birhor, Gond, Ho, Kharia, Mal Pahariya, Mundas, Oraon and Santhali represent the various aboriginal groups present in the district. The use of medicinal plants were documented using an interview data sheet mentioning the names, age, profession and gender of the informants and scientific and vernacular names, families, part(s) used, disease(s) treated, method of preparation, mode of administration of the botanicals and the preparations.

RESULTS

A total number of 56 plants belonging to 29 families have been reported to be used against different types of gastrointestinal disorders viz. indigestion, stomach pain, vomiting tendency, constipation, piles, diarrhea, dysentery, cholera, loss of appetite, liver complaints, intestinal worms etc. Fabaceae and Apocynaceae were found to be the dominant families of medicinal plants used to treat such ailments.

CONCLUSION

Age, gender, literacy and profession of the aboriginals were found to be the significant factors when the traditional knowledge of medicinal botanicals was concerned. Due to urbanization and loss of biodiversity, the authors have noted a significant decrease in the ethnic knowledge as well as the botanicals. Preservation of folklore should be given utmost importance in this region to prevent the rapid loss of ethnobotanical wealth.

Black tea and theaflavins assist healing of indomethacin-induced gastric ulceration in mice by antioxidative action

The healing activities of black tea (BT) and the theaflavins (TF) against the indomethacin-induced stomach ulceration were studied in a mouse model. Indomethacin (18 mg/kg, p.o.) administration induced maximum ulceration in the glandular portion of the gastric mucosa on the 3rd day, accompanied by increased lipid peroxidation and protein oxidation, depletion of thiol-defense and mucin, as well as reduced expressions of cyclooxygenases (COX) and prostaglandin (PG) E synthesis in the gastric tissues, and plasma total antioxidant status of mice. Treatment with BT (40 mg/kg), TF (1 mg/kg), and omeprazole (3 mg/kg) produced similar (74%-76%) ulcer healing, as revealed from the histopathological studies. Treatment with all the above samples reversed the adverse oxidative effects of indomethacin significantly. BT and TF also enhanced the PGE synthesis by augmenting the expressions of COX 1 and 2, but did not modulate acid secretion.