Preservation of immunological and biological activities of insulin by insulinase inhibitor in vitro

1970 ◽  
Vol 48 (5) ◽  
pp. 291-298
Author(s):  
J. Pierluissi ◽  
J. Campbell ◽  
K. S. Rastogi ◽  
G. R. Green ◽  
V. Lazdins

The relation of insulinase activity to the biological effect of insulin on isolated tissue was studied. Rat diaphragm in vitro caused the rapid disappearance of immunoreactive insulin (IRI) in physiological concentrations. IRI loss at time intervals was exponential. The fractional rate of loss of IRI was therefore independent of IRI concentration and was also approximately constant per milligram of tissue, the value being 0.0216%/mg∙mm. The value of the Michaelis constant (Km), obtained from initial velocities at five initial concentrations of IRI, was 1.85 × 10−8M, and of the maximal velocity (Vmax) was 2.32 × 10−11 mole/g∙min, based on insulin dimer. The addition of an insulinase inhibitor (a partial hydrolysate of insulin) to hemidiaphragm in vitro reduced the fractional rate of IRI loss by 60%. The increase in Km, without appreciable change in Vmax, indicated that the inhibition was competitive. The IRI preserved by means of the inhibitor was biologically active, since it increased the glycogen accumulation and the incorporation of 14C-U-glucose into glycogen in a second, fresh hemidiaphragm. In single incubation of hemidiaphragm with insulin, the gain in glycogen was correlated with the amount of inhibitor. The biological effect of insulin on diaphragm in vitro was therefore limited by tissue insulinase activity, and insulinase inhibitor potentiated to some extent the action of insulin.

2019 ◽  
Vol 25 (37) ◽  
pp. 4888-4902 ◽  
Author(s):  
Gilda D'Urso ◽  
Sonia Piacente ◽  
Cosimo Pizza ◽  
Paola Montoro

The consumption of berry-type fruits has become very popular in recent years because of their positive effects on human health. Berries are in fact widely known for their health-promoting benefits, including prevention of chronic disease, cardiovascular disease and cancer. Berries are a rich source of bioactive metabolites, such as vitamins, minerals, and phenolic compounds, mainly anthocyanins. Numerous in vitro and in vivo studies recognized the health effects of berries and their function as bioactive modulators of various cell functions associated with oxidative stress. Plants have one of the largest metabolome databases, with over 1200 papers on plant metabolomics published only in the last decade. Mass spectrometry (MS) and NMR (Nuclear Magnetic Resonance) are the most important analytical technologies on which the emerging ''omics'' approaches are based. They may provide detection and quantization of thousands of biologically active metabolites from a tissue, working in a ''global'' or ''targeted'' manner, down to ultra-trace levels. In the present review, we highlighted the use of MS and NMR-based strategies and Multivariate Data Analysis for the valorization of berries known for their biological activities, important as food and often used in the preparation of nutraceutical formulations.


Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2626
Author(s):  
Wael Sobhy Darwish ◽  
Abada El Sayed Khadr ◽  
Maher Abd El Naby Kamel ◽  
Mabrouk A. Abd Eldaim ◽  
Ibrahim El Tantawy El Sayed ◽  
...  

Ceratonia siliqua (Carob) is an evergreen Mediterranean tree, and carob pods are potentially nutritive and have medicinal value. The present study was carried out to estimate the possible biological activities of phytochemical-characterized carob pod aqueous extract (CPAE). The phytochemical contents of CPAE were determined by using colorimetric methods and HPLC. In addition, the free radical scavenging properties and anti-diabetic, anti-hemolytic, and antimicrobial activities were estimated by using standardized in vitro protocols. The phytochemical analysis revealed that CPAE was rich in polyphenols, flavonoids, and alkaloids, where it contained a significant amount of gallic acid, catechin, and protocatechuic acid. Furthermore, CPAE exhibited strong antioxidant activity where it prevented the formation of 2, 2-Diphenyl-1-picryl hydrazyl, hydroxyl, and nitric oxide free radicals. Additionally, it had a potent inhibitory effect against digestive enzymes (amylase, maltase, sucrase, and lactase). Moreover, CPAE exhibited anti-Staph aureus, anti-Escherichia coli, anti-Candida albicans, and anti-herpes simplex type I virus (HSV-I). Finally, CPAE protected the erythrocyte membrane from hypotonic solution-induced hemolysis. Altogether, CPAE could be regarded as an interesting source of biologically active antioxidant, anti-diabetic, and antimicrobial preparation for a potential application in pharmaceutical and food supplement fields.


Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3266 ◽  
Author(s):  
Gokhan Zengin ◽  
Luigi Menghini ◽  
Antonella Di Sotto ◽  
Romina Mancinelli ◽  
Francesca Sisto ◽  
...  

Due to renewed interest in the cultivation and production of Italian Cannabis sativa L., we proposed a multi-methodological approach to explore chemically and biologically both the essential oil and the aromatic water of this plant. We reported the chemical composition in terms of cannabinoid content, volatile component, phenolic and flavonoid pattern, and color characteristics. Then, we demonstrated the ethnopharmacological relevance of this plant cultivated in Italy as a source of antioxidant compounds toward a large panel of enzymes (pancreatic lipase, α-amylase, α-glucosidase, and cholinesterases) and selected clinically relevant, multidrug-sensible, and multidrug-resistant microbial strains (Staphylococcus aureus, Helicobacter pylori, Candida, and Malassezia spp.), evaluating the cytotoxic effects against normal and malignant cell lines. Preliminary in vivo cytotoxicity was also performed on Galleria mellonella larvae. The results corroborate the use of this natural product as a rich source of important biologically active molecules with particular emphasis on the role exerted by naringenin, one of the most important secondary metabolites.


2007 ◽  
Vol 66 (2) ◽  
pp. 207-215 ◽  
Author(s):  
Ian T. Johnson

Epidemiological studies showing a protective effect of diets rich in fruits and vegetables against cancer have focused attention on the possibility that biologically-active plant secondary metabolites exert anti-carcinogenic activity. This huge group of compounds, now collectively termed ‘phytochemicals’, provides much of the flavour and colour of edible plants and the beverages derived from them. Many of these compounds also exert anti-carcinogenic effects in animal models of cancer, and much progress has been made in defining their many biological activities at the molecular level. Such mechanisms include the detoxification and enhanced excretion of carcinogens, the suppression of inflammatory processes such as cyclooxygenase-2 expression, inhibition of mitosis and the induction of apoptosis at various stages in the progression and promotion of cancer. However, much of the research on phytochemicals has been conducted in vitro, with little regard to the bioavailability and metabolism of the compounds studied. Many phytochemicals present in plant foods are poorly absorbed by human subjects, and this fraction usually undergoes metabolism and rapid excretion. Some compounds that do exert anti-carcinogenic effects at realistic doses may contribute to the putative benefits of plant foods such as berries, brassica vegetables and tea, but further research with human subjects is required to fully confirm and quantify such benefits. Chemoprevention using pharmacological doses of isolated compounds, or the development of ‘customised’ vegetables, may prove valuable but such strategies require a full risk–benefit analysis based on a thorough understanding of the long-term biological effects of what are often surprisingly active compounds.


Foods ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 422
Author(s):  
Madalina Neacsu ◽  
Vassilios Raikos ◽  
Yara Benavides-Paz ◽  
Sylvia H. Duncan ◽  
Gary J. Duncan ◽  
...  

Legumes are a source of health-promoting macro- and micronutrients, but also contain numerous phytochemicals with useful biological activities, an example of which are saponins. Epidemiological studies suggest that saponins may play a role in protection from cancer and benefit human health by lowering cholesterol. Therefore, they could represent good candidates for specialised functional foods. Following the consumption of a soya-rich high-protein weight-loss diet (SOYA HP WL), the concentrations of Soyasaponin I (SSI) and soyasapogenol B (SSB) were determined in faecal samples from human volunteers (n = 10) and found to be between 1.4 and 17.5 mg per 100 g fresh faecal sample. SSB was the major metabolite identified in volunteers’ plasma (n = 10) after consumption of the soya test meal (SOYA MEAL); the postprandial (3 h after meal) plasma concentration for SSB varied between 48.5 ng/mL to 103.2 ng/mL. The metabolism of SSI by the gut microbiota (in vitro) was also confirmed. This study shows that the main systemic metabolites of soyasaponin are absorbed from the gut and that they are bioavailable in plasma predominantly as conjugates of sapogenol. The metabolism and bioavailability of biologically active molecules represent key information necessary for the efficient development of functional foods.


2007 ◽  
Vol 54 (4) ◽  
pp. 805-811 ◽  
Author(s):  
Michał Manturewicz ◽  
Zbigniew Grzonka ◽  
Lenka Borovicková ◽  
Jirina Slaninová

Eleven oxytocin analogues substituted in position 4, 5 or 9 by tetrazole analogues of amino acids were prepared using solid-phase peptide synthesis method and tested for rat uterotonic in vitro and pressor activities, as well as for their affinity to human oxytocin receptor. The tetrazolic group has been used as a bioisosteric substitution of carboxylic, ester or amide groups in structure-activity relationship studies of biologically active compounds. Replacement of the amide groups of Gln(4) and Asn(5) in oxytocin by tetrazole analogues of aspartic, glutamic and alpha-aminoadipic acids containing the tetrazole moiety in the side chains leads to analogues with decreased biological activities. Oxytocin analogues in which the glycine amide residue in position 9 was substituted by tetrazole analogues of glycine had diminished activities as well. The analysis of differences in rat uterotonic activity and in the affinity to human oxytocin receptors of analogues containing either an acidic 5-substituted tetrazolic group or a neutral 1,5- or 2,5-tetrazole nucleus makes it possible to draw some new conclusions concerning the role of the amide group of amino acids in positions 4, 5 and 9 of oxytocin for its activity. The data suggest that the interaction of the side chain of Gln(4) with the oxytocin receptor is influenced mainly by electronic effects and the hydrogen bonding capacity of the amide group. Steric effects of the side chain are minor. Substitution of Asn(5) by its tetrazole derivative gave an analogue of very low activity. The result suggests that in the interaction between the amide group of Asn(5) and the binding sites of oxytocic receptor hydrogen bonds are of less importance than the spatial requirements for this group.


Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4941
Author(s):  
Abdelwahab Khalil ◽  
Basem H. Elesawy ◽  
Tarek M. Ali ◽  
Osama M. Ahmed

Insects of the order Hymenoptera have a defensive substance that contains many biologically active compounds. Specifically, venom from honeybees (Apis mellifera) contains many enzymes and peptides that are effective against various diseases. Different research papers stated the possibility of using bee venom (a direct bee sting or in an injectable form) in treating several complications; either in vivo or in vitro. Other reports used the active fractions of bee venom clinically or at labratory scale. Many reports and publications have stated that bee venom and its constituents have multiple biological activities including anti-microbial, anti-protozoan, anti-cancer, anti-inflammatory, and anti-arthritic properties. The present review aims to refer to the use of bee venom itself or its fractions in treating several diseases and counteracting drug toxicities as an alternative protocol of therapy. The updated molecular mechanisms of actions of bee venom and its components are discussed in light of the previous updated publications. The review also summarizes the potential of venom loaded on nanoparticles as a drug delivery vehicle and its molecular mechanisms. Finally, the products of bee venom available in markets are also demonstrated.


Author(s):  
Morog R. Maddah ◽  
Etimad A. Huwait ◽  
Abeer Ali Al-balawi ◽  
Said S. Moselhy ◽  
Maryam A. ALghamdi ◽  
...  

Background: Oxidative stress is defined as imbalance between oxidant and antioxidant ratio, that lead to oxidative damage of biologically active molecules, finally lead to different disease and initiate carcinogenesis. The drug discovery using natural products as medicinal plants or marine organism still an important target for recent research. This study investigated anticancer activity of algae extract obtained from Red sea at Jeddah. Materials and Methods: Aqueousand methanol extracts ofDictyotaciliolata(DC) were tested on HCT-116 and HepG2 cell lines using WST-1. Aqueous extract (AEDC) and methanol extract (MEDC) at doses 0.05, 0.1, 0.5, 1 mg/ml and positive control 0.3% H2O2 at doses 0.5 mg/ml for 24,48 and 72 h (for two cell lines). Results: AEDC showed the mosteffective antitumor activity against HCT116 and HePG2, the IC50 dose for HCT116 cells was 0.05 mg/ml at 72 h, while for the HePG2 it was 0.01 mg/ml at 72 h. These results showed that HePG2cells was more sensitive to the AEDC. However, IC50 for MEDC were 0.01 mg/ml for HCT116 and 0.05 for HepG2 at 48 Hrs. The algae extracts contain sulfated polysaccharides and different pigments as chlorophylls, carotenoids and phycobiliproteins. These pigments were approved as biological active biomolecules that exert different biological activities as antioxidants, antitumor and rich source of micronutrients. In addition, AEDC or MEDC exert apoptotic activity by increase activity of caspase 3 and 9 in HepG2. Conclusıon: The antitumor effect of AEDC or MEDC is promising for development of chemotherapeutic agent as effective with no side effects.


2021 ◽  
Vol 12 ◽  
Author(s):  
Fei Luan ◽  
Lixia Peng ◽  
Ziqin Lei ◽  
Xiyu Jia ◽  
Junbo Zou ◽  
...  

Averrhoa carambola L. (star fruit) is an edible fruit that is extensively cultivated in southern China, Southeast Asia, India, and northern South America. It has a sweet and juicy taste and is frequently used in fruit salads and fruit platters, as a garnish in cocktail drinks and beverages, or squeezed into juice and served as a beverage. Traditionally, it has been used for treating diabetes and diabetic nephropathy, arthralgia, vomiting, lithangiuria, coughing, hangovers, and chronic paroxysmal headache for thousands of years. Currently, approximately 132 compounds have been isolated from A. carambola. Among them, flavonoids, benzoquinone, and their glycosides have been considered as biologically active substances, which are responsible for various biological activities. Pharmacological studies have revealed that crude extracts or monomeric compounds from A. carambola exhibit multiple bioactivities, such as anti-oxidant, anti-hyperglycemic, anti-obesity, anti-hyperlipidemic, anti-tumor, anti-inflammatory, hepatoprotective, cardioprotective, anti-hypertensive, neuroprotective, and others. Thus, A. carambola is a valuable treatment in Chinese medicine with therapeutic potential for multiple diseases, especially diabetes and diabetes-related diseases. Even though it is a very promising candidate in the development of functional food and the pharmaceutical industry, reports on its bioactivities have only been conducted in vivo and in vitro and there is a gap in research regarding clinical settings and safety. This review therefore provides a comprehensive and systematic overview of current progress on botany, ethnopharmacology, phytochemistry, pharmacology, and toxicity of A. carambola, providing a valuable reference for further developments and applications of A. carambola in the pharmaceutical industry and functional food.


Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5032
Author(s):  
Soukaina Hrichi ◽  
Raja Chaabane-Banaoues ◽  
Sihem Bayar ◽  
Guido Flamini ◽  
Yassine Oulad El Majdoub ◽  
...  

Scarce information about the phenolic composition of Scabiosa atropurpurea L. is available, and no carotenoid compounds have been reported thus far. In this study the phenolic and carotenoid composition of this plant was both investigated and associated bioactivities were evaluated. Aiming to obtain extracts and volatile fractions of known medicinal plants to valorize them in the pharmaceutical or food industries, two techniques of extraction and five solvents were used to determine the biologically active compounds. Gas chromatography coupled to flame ionization and mass spectrometry and liquid chromatography coupled to photodiode array and atmospheric pressure chemical ionization/electrospray ionization mass spectrometry highlighted the presence of 15 volatiles, 19 phenolics, and 24 natural pigments in Scabiosa atropurpurea L. stem samples; among them, the most abundant were 1,8-cineole, chlorogenic acid, cynaroside, and lutein. Bioactivity was assessed by a set of in vitro tests checking for antioxidant, antibacterial, antifungal, and allelopathic (against Brassica oleracea L. and Lens culinaris Medik) effects. Scabiosa atropurpurea L. stem extracts presented a considerable antioxidant, antibacterial, and allelopathic potential, with less antifungal effectiveness. These results indicate that the volatile fractions and extracts from S. atropurpurea L. stem could be considered as a good source of bioactive agents, with possible applications in food-related, agriculture, and pharmaceutical fields. Genetic investigations showed 97% of similarity with Scabiosa tschiliensis, also called Japanese Scabiosa.


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