Effects Of Kefir Research Articles

Kefirin Obezite ve Diyabet Üzerine Etkileri

Özet Son on yılda obezite, diyabet, dislipidemi gibi kronik bulaşıcı olmayan hastalık vakalarındaki artışla birlikte tamamlayıcı veya adjuvan tedavi olarak probiyotik ve prebiyotik kullanımına ilgi artmıştır. Kefir probiyotik içeriği zengin fermente bir üründür. Probiyotik içeriği zengin bir fermente ürün olan kefirin diyabet üzerindeki etkileri incelemek amacıyla son on yılda yapılan çalışmalar incelenmiş ve derlenmiştir. Sonuçlar değerlendirildiğinde farklı dozlarda ve farklı sürelerde günlük olarak tüketilen kefirin iyi bir glisemik kontrol ve metabolik kontrol sağlayıcı olduğu incelenen çalışmalarda belirtilmektedir. Yapılan bu derleme çalışması ile hedeflenen ileriki çalışmalarda farklı süt türleri ve farklı bakteri suşları kullanılarak üretilen kefirlerin insan sağlığının farklı boyutlardaki etkilerinin incelenmesine (merkezi sinir sistemi gibi) ve kefirin raf ömrü gibi kriterlerine etkisine ışık tutması amaçlanmaktadır.

Effects of kefir on liver function tests and histopathological changes in rats exposed to aflatoxin B1

Effects of kefir on liver function tests and histopathological changes in rats exposed to aflatoxin B1

Changes in hepatic thiol contents and regulation of glutathione S-transferase by high-fructose diet: Effects of kefir and some probiotic bacteria

In this study, thiol/disulfide homeostasis in the liver tissues of high-fructose-fed rats was investigated in conjunction with the changes in the main hepatic detoxification enzyme, glutathione S-transferase (GST). Additionally, the effects of well-known probiotics namely Kefir, Lactobacillus helveticus, and Lactobacillus plantarum supplementation on the thiol/disulfate contents and GST activity and gene expression levels were analyzed. Fructose, administered as a 20% solution in drinking water for 15 weeks, developed an animal model of metabolic syndrome in male Wistar rats. Kefir, L. helveticus, and L. plantarum supplementations were given by gastric gavage once a day during the final 6-weeks. The changes in hepatic GST were determined with kinetic-optimized spectrophotometric enzyme assays and qRT-PCR. Total thiol, native thiol, and disulfide levels were analyzed using (5,5-dithio-bis-(2-nitrobenzoic acid) as a chromogenic agent. High-fructose consumption reduced total and native thiol contents while increasing disulfide levels in the liver tissues of rats. Kefir and L. plantarum normalized the thiol levels and all probiotics reduced disulfide contents. High fructose augmented total GST activity but reduced the GST-Mu isoform. L. helveticus and L. plantarum normalized the total and GST-Mu activity, respectively. These results demonstrated a shift toward disulfide formation in the hepatic tissues of rats fed with high fructose. A possible reason would be the increase in total GST activity that uses the free glutathione, the main native thiol source in cells, as a substrate. Besides, probiotics such as Kefir, L. helveticus, and L. plantarum have an improving effect on thiol/disulfide homeostasis as well as main detoxification enzymes.

The effects of kefir in mixed meals on appetite and food intake: a randomized cross-over trial

ABSTRACT Objective The natural probiotic kefir is fermented milk, and may have effects on satiety and voluntary energy intake. This randomized crossover trial aimed to determine whether kefir, consumed with low- or high-glycemic index meals, affects appetite and subsequent food intake. Methods Twenty four healthy females aged 21-24 years, were recruited from Erciyes University and the surrounding community. The participants were submitted to three different breakfasts: a low glycemic index accompanied by milk, a low glycemic index with kefir, and a high glycemic index with kefir, with a 1-week washout period between meals. At 0, 15, 30, 60, 90, 120, 150, and 180 minutes after the meal, appetite ratings were measured by the visual analog scale, and then ad libitum lunch was served. Results No differences in appetite scores and voluntary energy intake were detected between the test meals. Furthermore, palatability ratings were similar between test meals, except for the higher score of high glycemic index kefir for overall palatability. Conclusion This study demonstrated that adding kefir to a high glycemic index meal may prevent increases in appetite and food intake, resulting in postprandial responses similar to those of a low glycemic index meal. These findings might enable the development of novel dietary strategies based on appetite regulation to treat or prevent obesity, particularly for Western societies. This trial was registered at ClinicalTrials.gov under the process NCT03636217.

Effects of kefir or milk supplementation on zonulin in overweight subjects

Increased intestinal permeability has been shown to be involved in several diseases associated with low-grade chronic inflammation, including obesity and metabolic syndrome. In the last decade, growing evidence shows the beneficial effects of probiotic-containing food supplementation on these conditions. In this crossover intervention study on 28 asymptomatic overweight adults, we tested the effects of a 3-wk kefir supplementation compared with a 3-wk milk supplementation on serum zonulin levels. The effects on serum glucose, triacylglycerols, low-density lipoproteins, high-density lipoproteins, total cholesterol, markers of inflammation (C-reactive protein and adiponectin), anthropometric variables, mood, and appetite were also determined. Kefir supplementation resulted in a greater improvement of serum zonulin levels (F = 6.812, η2 = 0.275), whereas a significant yet similar improvement in lipid profile and serum glucose levels was found in both supplementations. Positive mood was slightly but significantly enhanced with kefir supplementation, and reduced with milk supplementation. The C-reactive protein, adiponectin, and appetite were unaffected. In conclusion, supplementation with both dairy products had health beneficial effects, but only kefir showed an effect on the intestinal barrier dysfunction marker.

Probiotic Kefir Antihypertensive Effects in Spontaneously Hypertensive Rats Involves Central and Peripheral Mechanisms

Gut microbiota dysbiosis has been associated with hypertension. Long‐term use of probiotics have been shown to decrease blood pressure, improve baroreflex, and ameliorate endothelial dysfunction in Spontaneously Hypertensive Rats (SHR). Yet, the mechanisms are not well understood. We aimed to evaluate peripheral and centrally mediated mechanisms by which the probiotic kefir promotes beneficial effects in SHRs. We used Wistar Kyoto (WKY) and SHR male rats, divided into: WKY and SHR treated with vehicle, and SHR treated with milk fermented by the kefir grains (5%; SHR‐Kefir; oral gavage, daily/9 weeks). We evaluated blood pressure by tail cuff method weekly. The effects of kefir were evaluated on gut anatomy (histological analysis of the small intestine), gut microbiota composition (microbiological analysis of the feces), and endotoxin levels (Lipopolysaccharide (LPS) content analyzed in serum). Within the paraventricular nucleus of the hypothalamus (PVN), we evaluated microglia activation and tyrosine hydroxylase (TH) protein expression via immunofluorescence. TH mRNA levels were analyzed via real time PCR. SHR‐Kefir presented a lower mean blood pressure (151.9±2.9mmHg) compared to SHR (173.1±2.41mmHg, P<0.0001 n=6). Basal gut microbiota composition in SHRs differed from that observed for WKY, suggesting dysbiosis. Treatment with kefir restored the normal gut microbiota composition profile of Lactobacillus, Staphylococcus, Brucella and Bifidobacterium spp. The number of Paneth cells/crypt was decreased in SHR (1.66±0.06) compared to WKY (2.40±0.08 p<0.0004), an effect which was normalized with kefir treatment (SHR‐Kefir:2.23±0.15). An increase in LPS serum content in SHR (0.71±0.02) compared to WKY (0.54±0.04 EU/mL p<0.01), suggesting increased intestinal permeability during hypertension, was reversed in SHR‐Kefir (0.54±0.01). Within the PVN, microglia density was used as an indication of microglia activation. We found increased microglia activation in SHR (9.47±0.61) compared to WKY (6.87±0.68 p<0.07), which was normalized in SHR‐Kefir rats (4.77±0.55, arbitrary units [AU]). TH protein overexpression observed in SHRs was reduced with treatment of probiotic (WKY: 5.25±0.58; SHR: 13.68±0.81 and SHR‐Kefir: 8.42±0.55, AU p<0.0001). The mRNA expression of TH within the PVN (punches) was increased in SHR by 47%. Kefir treatment decreased mRNA TH expression (WKY: 1.21±0.45; SHR: 1.79±0.50; SHR‐Kefir: 1.30±0.27 fold change). Our data shows that kefir treatment in SHRs restores gut microbiota composition and intestinal structure, diminishes levels of serum endotoxin, reduces neuroinflammation, and balances levels of tyrosine hydroxylase within the hypothalamus. Altogether, our data suggests that kefir antihypertensive‐associated mechanisms involves gut microbiota–brain axis communication during hypertension.Support or Funding InformationThis work was funded by CAPES PDSE 88881.133261/2016‐01 to MAS. VCB is funded by AHA 14SDG20400015.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Fates of Salmonella Enteritidis and Cronobacter sakazakii in various multiple‐strain yogurts and kefir during cold storage

AbstractMany multiple‐strain fermented milks such as yogurt and kefir have been developed and consumed to improve their nutritional and functional benefits. Since these fermented milks can be a vehicle of foodborne illness, we investigated the fates of Salmonella Enteritidis and Cronobacter sakazakii in four fermented milks: multiple‐lactic acid bacteria (multi‐LAB) yogurt, multiple‐LAB‐Bifidobacterium (multi‐LAB‐BIF) yogurt, pH 4.5 kefir (mild kefir), and pH 3.6 kefir (strong kefir). Each was inoculated with 5.6 and 5.8 log cfu/ml of S. Enteritidis and C. sakazakii, respectively, and stored at 4°C for 5 days. Strong and mild kefirs exhibited more potent antimicrobial activities than multi‐LAB and multi‐LAB‐BIF yogurts, inactivating all viable pathogenic bacteria within 1 and 5 days, respectively. Despite having lower pH values than mild kefir (pH 4.49), multi‐LAB (pH 4.25) and multi‐LAB‐BIF (pH 4.38) yogurts failed to clear viable S. Enteritidis cells in 5 days (> 5 log cfu/ml cells survived).Practical applicationsYogurt is one of the most popular fermented milk, and has been implicated in several human foodborne outbreaks. Kefir is unique fermented milk containing multiple strains of lactic acid bacteria and yeast. In this study, we investigated the fates of Salmonella Enteritidis and Cronobacter sakazakii in these fermented milks. Two types of commercial yogurt failed to clear viable S. Enteritidis cells in 5 days, whereas kefir successfully killed all viable S. Enteritidis and C. sakazakii cells in 5 and 4 days, respectively, even with significantly higher pH values suggesting that pH might not be a suitable indicator to ensure the microbiological safety of yogurts and kefir, and that pathogens face other antimicrobial hurdles than low pH and high acidity. Considering the potent self‐clearance effects of kefir against foodborne pathogens, novel yogurt products containing strains with potent antimicrobial activity such as kefir microorganisms could be newly developed in the future.

Kefir alleviates obesity and hepatic steatosis in high-fat diet-fed mice by modulation of gut microbiota and mycobiota: targeted and untargeted community analysis with correlation of biomarkers

Kefir is a probiotic beverage containing over 50 species of lactic acid bacteria and yeast. In this study, the anti-obesity and anti-non-alcoholic fatty liver disease (NAFLD) effects of kefir were comprehensively addressed along with targeted and untargeted community analysis of the fecal microbiota in a high-fat diet (HFD)-induced obese mouse model. HFD-fed C57BL/6 mice were orally administrated either kefir or milk (control) once a day for 12 weeks, and body and organ weight, fecal microbiota and mycobiota, histopathology, blood cholesterol and cytokines and gene expressions were analyzed. Compared to the control, mice in the kefir group exhibited a significantly lower body weight (34.18 g vs. 40.24 g; p=0.00004) and histopathological liver lesion score (1.13 vs. 3.25; p=0.002). Remarkably, the kefir-fed mice also harbored more Lactobacillus/Lactococcus (7.01 vs. 6.32 log CFU/g), total yeast (6.07 vs. 5.01 log CFU/g) and Candida (5.56 vs. 3.88 log CFU/g). Kefir administration also up-regulated genes related to fatty acid oxidation, PPARα and AOX, in both the liver and adipose tissue (PPARα, 2.95- and 2.15-fold; AOX, 1.89- and 1.9-fold, respectively). The plasma concentration of IL-6, a proinflammatory marker, was significantly reduced following kefir consumption (50.39 pg/ml vs. 111.78 pg/ml; p=0.03). Strikingly, the populations of Lactobacillus/Lactococcus, total yeast and Candida were strongly correlated with PPARα gene expression in adipose and hepatic tissue (r=0.599, 0.580 and 0.562, respectively). These data suggest that kefir consumption modulates gut microbiota and mycobiota in HFD-fed mice, which prevents obesity and NAFLD via promoting fatty acid oxidation.

Effects of Kefir on the Cardiac Autonomic Tones and Baroreflex Sensitivity in Spontaneously Hypertensive Rats.

Aims: It has been previously shown that the probiotic kefir (a symbiotic matrix containing acid bacteria and yeasts) attenuated the hypertension and the endothelial dysfunction in spontaneously hypertensive rats (SHR). In the present study, the effect of chronic administration of kefir on the cardiac autonomic control of heart rate (HR) and baroreflex sensitivity (BRS) in SHR was evaluated.Methods: SHR were treated with kefir (0.3 mL/100 g body weight) for 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Cardiac autonomic vagal (VT) and sympathetic (ST) tones were estimated through the blockade of the cardiac muscarinic receptors (methylatropine) and the blockade of β1−adrenoceptor (atenolol). The BRS was evaluated by the tachycardia and bradycardia responses to vasoactive drug-induced decreases and increases in arterial blood pressure (BP), respectively. Additionally, spontaneous BRS was estimated by autoregressive spectral analysis.Results: Kefir-treated SHR exhibited significant attenuation of basal BP, HR, and cardiac hypertrophy compared to non-treated SHR (12, 13, and 21%, respectively). Cardiac VT and ST were significantly altered in the SHR (~40 and ~90 bpm) compared with Wistar rats (~120 and ~30 bpm) and were partially recovered in SHR-kefir (~90 and ~25 bpm). SHR exhibited an impaired bradycardic BRS (~50%) compared with Wistar rats, which was reduced to ~40% in the kefir-treated SHR and abolished by methylatropine in all groups. SHR also exhibited a significant impairment of the tachycardic BRS (~23%) compared with Wistar rats and this difference was reduced to 8% in the SHR-kefir. Under the action of atenolol the residual reflex tachycardia was smaller in SHR than in Wistar rats and kefir attenuated this abnormality. Spectral analysis revealed increased low frequency components of BP (~3.5-fold) and pulse interval (~2-fold) compared with Wistar rats and these differences were reduced by kefir-treatment to ~1.6- and ~1.5-fold, respectively. Spectral analysis also showed an impairment of spontaneous BRS in SHR, but kefir-treatment caused only a tendency to reverse this result.Conclusions: The novelty of this study is that daily chronic consumption of a low dose of kefir reduced the impairment of the cardiac autonomic control of HR and of the impaired BRS in SHR.

Kefir and Cancer: A Systematic Review of Literatures.

Some studies have suggested chemopreventive effects of kefir, a fermented milk product, on carcinogenesis. The aim of this review study was to evaluate the scientific evidence for effects of kefir on cancer prevention and treatment. We systematically searched for all relevant studies published before June 2015, using PubMed, Google scholar, Cochrane and Science Direct, SID, MedLib and Srlst databases. Relevant studies were reviewed based on systematic review (PRISMA) guidelines. From a total of 2208 papers obtained at the initial database search, 11 publications including 7 in vitro and 4 experimental studies were eligible. In vitro studies on breast, colon, skin and gastric cancers and leukemia cell lines and experimental studies on different sarcomas consistently showed beneficial effects of kefir on cancer prevention and treatment. The results of this systematic review suggest that kefir may be associated with cancer prevention and it also has beneficial effects in cancer treatment. This protection may be associated with kefir bioactive components including peptides, polysaccharides and sphingolipids.

Effects of Kefir, Koumiss, Milk and Yoghurt Administration on Distribution of Plasma Cells and Mast Cells in Mice Spleen

Effects of Kefir, Koumiss, Milk and Yoghurt Administration on Distribution of Plasma Cells and Mast Cells in Mice Spleen

Immunohistochemical examination of effects of kefir, koumiss and commercial probiotic capsules on platelet derived growth factor-c and platelet derived growth factor receptor-alpha expression in mouse liver and kidney

We investigated using immunohistochemistry the effects of kefir, koumiss and commercial probiotic capsules on the expression of platelet derived growth factor-c (PDGF-C) and platelet derived growth factor receptor-alpha (PDGFR-α) in mouse liver and kidney. Mice were assigned to four groups: group 1 was given commercial probiotic capsules, group 2 was given kefir, group 3 was given koumiss and group 4 was untreated. After oral administration for 15 days, body weights were recorded and liver and kidney tissue samples were obtained. Hematoxylin and eosin staining was used to examine histology. PDGF-C and PDGFR-α in liver and kidney were localized using the streptavidin-biotin peroxidase complex method (ABC). We found that the weights of the mice in the kefir, koumiss and commercial probiotic capsules groups increased compared to the control group. No differences in liver and kidney histology were observed in any of the experimental groups. Kefir, koumiss and the commercial probiotic preparation increased PDGF-C and PDGFR-α expression.

Anticancer activities of kefir against LMS and K562 cell lines by flow cytometry analysis

PurposeKefir is a probiotic grown with milk, with a slightly sour flavor and has been consumed for thousands of years. Kefir grains contain bacteria and yeast. In the past, kefir was administrated as a drug against tuberculosis, cancer and gastrointestinal disorders. The purpose of this paper is to investigate the potential anticancer properties of kefir and its ability to affect natural killer cells' (NKCs') activity.Design/methodology/approachThe assay of cytotoxic activity of NKCs by cytometric analysis was used, which included four stages: isolation of natural killers; quantification of target cells; incubation of natural killers with target cells at ratios of 12.5:1, 25:1 and 50:1 in CO2 incubator; and measurement of cells with flow cytometer. The same procedures were repeated, but the third stage was modified with the addition and incubation of 50, 75, and 100 μL kefir (of 24 hour culture with 3.5 per cent fresh milk) with K562 and leiomyosarcoma cells lines, and kefir and NK cells with K562 or LMS cell lines.FindingsThe results showed that kefir's cytotoxic activity without the presence of NKCs reached an average of 85 per cent in both cell lines. With the addition of NK cells in kefir, the cytotoxic activity further increased by 10 per cent. Kefir alone did not cause any statistically significant death in NK cells. Kefir seems to have significant cytotoxic action by itself without stimulating NK cells in a significant manner. However, further studies are needed to establish the role of kefir in the prevention and treatment of neoplasmatic diseases.Originality/valueThe paper provides information and new data, for nutritionists and clinical dietitians, about the effects of kefir in the prevention of cancer.

Effects of kefir on coccidial oocysts excretion and performance of dairy goat kids following weaning

The aim of this study was to investigate effects of kefir, a traditional source of probiotic, on coccidial oocysts excretion and on the performance of dairy goat kids following weaning. Twin kids were randomly allocated to one of two groups at weaning. Kids of the first group received 20 ml of kefir daily for 6 weeks (KEF), while kids in the control group were given a placebo (CON). Individual faecal samples were regularly (n = 18 per kid) taken to quantify the number of coccidial oocysts per gram of faeces (OpG). There were no differences between the groups in terms of body weight development (P > 0.05) and feed consumption. Kids of both groups were not able to consume enough feed to meet their nutrient requirements during the first 3 weeks following weaning. KEF had a lower frequency of OpG positive samples than CON (P = 0.043). Kefir did not affect the maximum oocyst excretion and age of the kids at the highest oocyst excretion (P > 0.05). KEF shed numerically 35% lower coccidial oocysts than the controls, which corresponded to a statistical tendency (P = 0.074) in lowering Log-OpG in comparison to CON. While KEF had a lower frequency of OpG positive samples and tended to shed lower OPG by around one-third, the frequency of diarrhea, level of highest oocyst excretion, and performance of the kids remained unaffected. Therefore, it is concluded that overall effects of kefir do not have a significant impact on sub-clinical infection and performance in weaned kids under relatively high-hygienic farming conditions.

Intestinal beneficial effects of kefir-supplemented diet in rats

Kefir is considered to be probiotic, beneficially affecting the host through its effects in the intestinal tract. Despite numerous studies that have examined the actions of probiotics on the host organism, few have analyzed the effects on intestinal enzymes. The aim of this present study is to report data on the effects of kefir on enzymes and proteins present in the intestine. In this study, female rats were fed for 22 days with 2 types of diets, standard and kefir-supplemented. Food intake and body weight were recorded daily. The glucose, uric acid, cholesterol, triacylglycerols, and alkaline phosphatase activity were measured in the serum. Rat body weights were similar in both groups (control and kefir). No significant differences were found in the weight of the organs examined. An intestinal enzymatic analysis was carried out, and the results showed an increase of this activity in addition to the uptake of d -galactose by brush border membrane vesicles. Glycemia was significantly lower in the kefir group. The present findings indicate that kefir, in the conditions studied, could benefit protein digestion and reduce glycemic index.