Effect of camel milk on lipid profile among patients with diabetes: a systematic review, meta-analysis, and meta-regression of randomized controlled trials

The effects of camel milk (CM) intake on lipid profile among patients with diabetes remain controversial. This systematic review and meta-analysis of randomized controlled trials (RCTs) aimed to calculate the effect size of CM intake on blood lipids among patients with type 1 (T1D) and type 2 (T2D) diabetes. We searched nine databases from inception until December 31, 2022, to identify relevant RCTs. Effect sizes for total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), and high-density lipoprotein (HDL) were calculated and expressed using mean differences (MD) and confidence intervals (CI). Of 4,054 retrieved articles, 10 RCTs (a total of 347 participants aged 8-70 years, 60.5% male) were eligible for inclusion. The pooled results from a random-effects model showed statistically significant decreases in TC (MD - 21.69, 95% CI: 41.05, - 2.33; p = 0.03; I2=99%), TG (MD - 19.79, 95% CI: -36.16, - 3.42; p=0.02, I2=99%), and LDL (MD -11.92, CI: -20.57, -3.26; p = 0.007, I2=88%), and a significant increase in HDL (MD 10.37, 95% CI, 1.90, 18.84; p=0.02, I2=95%) in patients with diabetes supplemented with CM compared with usual care alone. Subgroup analysis revealed that only long-term interventions (> 6 months) elicited a significant reduction in TC levels and TG levels. Consumption of fresh CM by patients with diabetes resulted in significant reductions in TC, TG, and LDL levels, while showing a significant increase in HDL levels. Patients with T1D elicited a more beneficial effect in lowering TC, LDL, and TG levels and in increasing HDL levels than their corresponding partners with T2D. In conclusion, long-term consumption of CM for patients with diabetes, especially those with T1D, could be a useful adjuvant therapy to improve lipid profile alongside prescribed medications. However, the high heterogeneity in the included studies suggests that more RCTs with larger sample sizes and longer intervention durations are required to improve the robustness of the available evidence.

Fermented camel milk enriched with plant sterols improves lipid profile and atherogenic index in rats fed high -fat and -cholesterol diets

The current study was designed to explore the effect of fermented camel milk, plant sterols and their combination on the blood levels of sd-LDL and atherogenicity in rats fed on high-fat-cholesterol diets (HFC). Forty male Wistar rats were distributed into five groups: Normal control (NC), Positive control (PC, HFC), plant sterol (PS, HFC containing 1% (w/w) β-sitosterol:Stigmasterols; 9:1), FM (HFC containing 4% (w/w) lyophilized fermented camel milk), and PSFM (HFC containing 1% (w/w) plant sterols +4% (w/w) lyophilized fermented camel milk). Antioxidant activity showed that β-sitosterol had the highest radical scavenging activity, followed by fermented camel milk and stigmasterol (p < 0.05). Feeding rats on HFC for 8 weeks resulted in a significant (p < 0.05) increase in blood lipids of PC group compared with NC group. Administration of PS, FM, and PSFM resulted in a significant reduction in atherogenic index (50, 24.5, and 41.5 %, p < 0.05), and sd-LDL levels (73, 45, and 59%, p < 0.05), respectively. Only the FM group showed a significant reduction in triglycerides levels of rats. Administration of PS, FM and PSFM decreased serum MDA levels significantly by 58.7, 45.4, and 69% (p < 0.05), and increased total antioxidant capacity by 35.9, 84.8, and 38.3% (p < 0.05), respectively. This is the first report to the best of our knowledge that shows fermented camel milk enriched with plant sterol could reduce atherogenesis and cardiovascular diseases activity via inhibition of the status of small dense LDL and oxidative stress.

Beneficial Effects of Fermented Camel and Cow’s Milk in Lipid Profile, Liver, and Renal Function in Hypercholesterolemic Rats

As hyperlipidemia has been associated with cardiovascular diseases, this study investigated the influence of probiotic-fermented camel and cow’s milk on blood lipid profiles in hypercholesterolemic rats. When tested, probiotic-fermented camel and cow’s milk exhibited the highest overall acceptance score in flavor and texture. Forty-eight male Wistar rats were divided into eight groups (n = 6). The first group served as normal control, while groups 2–8 were fed on a high-fat (HFD), high-cholesterol diet throughout the experimental period and treated with different types of fermented milks. Feeding rats on probiotic-fermented milk resulted in a significant decrease in the level of triglycerides (TG), cholesterol, and LDL compared with the positive control group. Albumin and total protein concentrations increased significantly, while ALT, AST, and creatinine were significantly reduced in rats fed on probiotic-fermented milk. The results indicated that probiotic-fermented milk might improve liver and kidney functions in hypercholesterolemic rats. These findings highlighted the ameliorative potentials of camel milk against hyperlipidemia and oxidative stress in rats.

A Comprehensive Review of the Composition, Nutritional Value, and Functional Properties of Camel Milk Fat

Recently, camel milk (CM) has been considered as a health-promoting icon due to its medicinal and nutritional benefits. CM fat globule membrane has numerous health-promoting properties, such as anti-adhesion and anti-bacterial properties, which are suitable for people who are allergic to cow's milk. CM contains milk fat globules with a small size, which accounts for their rapid digestion. Moreover, it also comprises lower amounts of cholesterol and saturated fatty acids concurrent with higher levels of essential fatty acids than cow milk, with an improved lipid profile manifested by reducing cholesterol levels in the blood. In addition, it is rich in phospholipids, especially plasmalogens and sphingomyelin, suggesting that CM fat may meet the daily nutritional requirements of adults and infants. Thus, CM and its dairy products have become more attractive for consumers. In view of this, we performed a comprehensive review of CM fat's composition and nutritional properties. The overall goal is to increase knowledge related to CM fat characteristics and modify its unfavorable perception. Future studies are expected to be directed toward a better understanding of CM fat, which appears to be promising in the design and formulation of new products with significant health-promoting benefits.

Camel milk: alternative milk for human consumption and its health benefits

Purpose

– Camel as a livestock plays an important role in desert ecosystem and its milk has potential contribution in human nutrition in the hot and arid regions of the world. This milk contains all the essential nutrients as found in other milk. Fresh and fermented camel milk has been used in different regions in the world including India, Russia and Sudan for human consumption as well as for treatment of a series of diseases such as dropsy, jaundice, tuberculosis, asthma and leishmaniasis or kala-azar. The present paper aims to explore the possibility of camel milk as an alternative milk for human consumption.

Design/methodology/approach

– Recently, camel milk and its components were also reported to have other potential therapeutic properties, such as anti-carcinogenic, anti-diabetic, anti-hypertensive and renoprotective potential; and for autism, and has been recommended to be consumed by children who are allergic to bovine milk.

Findings

– It has also been reported to alleviate oxidative stress and lipid peroxidation in rats. Camel milk differs from bovine milk in composition. It contains low total solids and fat; however, proteins and lactose are in equal amount but of higher quality than cow milk. Because of the high percentage of β-casein, low percentage of α-casein, deficiency of β-lactoglobulin and similarity of the immunoglobulins, it become safer for persons who are allergic to bovine milk. It contains protective proteins in higher amount which contributes to its functionality. The fermentation and enzymatic hydrolysis of camel protein produce different types of bioactive peptides which exerts different activity in in vitro and in vivo conditions.

Originality/value

– Because of its unique quality and functionality, this milk has potential application in management of different diseases and application in food industries.

Supplementation of Lactobacillus plantarum K68 and Fruit-Vegetable Ferment along with High Fat-Fructose Diet Attenuates Metabolic Syndrome in Rats with Insulin Resistance

Lactobacillus plantarum K68 (isolated from fu-tsai) and fruit-vegetable ferment (FVF) have been tested for antidiabetic, anti-inflammatory, and antioxidant properties in a rat model of insulin resistance, induced by chronic high fat-fructose diet. Fifty rats were equally assigned into control (CON), high fat-fructose diet (HFFD), HFFD plus K68, HFFD plus FVF, and HFFD plus both K68 and FVF (MIX) groups. Respective groups were orally administered with K68 (1 × 10⁹ CFU/0.5 mL) or FVF (180 mg/kg) or MIX for 8 weeks. We found that HFFD-induced increased bodyweights were prevented, and progressively increased fasting blood glucose and insulin levels were reversed (P < 0.01) by K68 and FVF treatments. Elevated glycated hemoglobin (HbA1c) and HOMA-IR values were controlled in supplemented groups. Furthermore, dyslipidemia, characterized by elevated total cholesterol (TC), triglyceride (TG), and low-density lipoproteins (LDLs) with HFFD, was significantly (P < 0.01) attenuated with MIX. Elevated pro-inflammatory cytokines, interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α), were controlled (P < 0.01) by K68, FVF, and MIX treatments. Moreover, decreased superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities were substantially (P < 0.01) restored by all treatments. Experimental evidences demonstrate that K68 and FVF may be effective alternative medicine to prevent HFFD-induced hyperglycemia, hyperinsulinemia, and hyperlipidemia, possibly associated with anti-inflammatory and antioxidant efficacies.

Effect of probiotic yogurt containing Lactobacillus acidophilus and Bifidobacterium lactis on lipid profile in individuals with type 2 diabetes mellitus

The purpose of this study was to investigate the effects of probiotic and conventional yogurt on the lipid profile in type 2 diabetic people. In a randomized double-blind controlled trial, 60 people (23 males and 37 females) with type 2 diabetes and low-density lipoprotein cholesterol (LDL-C) greater than 2.6 mmol/L were assigned to 2 groups. Participants consumed daily 300 g of probiotic yogurt containing Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 or 300 g of conventional yogurt for 6 wk. Fasting blood samples, anthropometric measurements and 3-d, 24-h dietary recalls were collected at the baseline and at the end of the trial. Probiotic yogurt consumption caused a 4.54% decrease in total cholesterol and a 7.45% decrease in LDL-C compared with the control group. No significant changes from baseline were shown in triglyceride and high-density lipoprotein cholesterol (HDL-C) in the probiotic group. The total cholesterol:HDL-C ratio and LDL-C:HDL-C ratio as atherogenic indices significantly decreased in the probiotic group compared with the control group. Probiotic yogurt improved total cholesterol and LDL-C concentrations in type 2 diabetic people and may contribute to the improvement of cardiovascular disease risk factors.

Antiobesity and lipid-lowering effects of Bifidobacterium spp. in high fat diet-induced obese rats

BACKGROUND

Recent studies have reported the preventive effects of probiotics on obesity. Among commensal bacteria, bifidobacteria is one of the most numerous probiotics in the mammalian gut and are a type of lactic acid bacteria. The aim of this study was to assess the antiobesity and lipid-lowering effects of Bifidobacterium spp. isolated from healthy Korean on high fat diet-induced obese rats.

METHODS

Thirty-six male Sprague-Dawley rats were divided into three groups as follows: (1) SD group, fed standard diet; (2) HFD group, fed high fat diet; and (3) HFD-LAB group, fed high fat diet supplemented with LAB supplement (B. pseudocatenulatum SPM 1204, B. longum SPM 1205, and B. longum SPM 1207; 108 ~ 109 CFU). After 7 weeks, the body, organ, and fat weights, food intake, blood serum levels, fecal LAB counts, and harmful enzyme activities were measured.

RESULTS

Administration of LAB reduced body and fat weights, blood serum levels (TC, HDL-C, LDL-C, triglyceride, glucose, leptin, AST, ALT, and lipase levels), and harmful enzyme activities (β-glucosidase, β-glucuronidase, and tryptophanase), and significantly increased fecal LAB counts.

CONCLUSION

These data suggest that Bifidobacterium spp. used in this study may have beneficial antiobesity effects.

Lactic acid bacteria affect serum cholesterol levels, harmful fecal enzyme activity, and fecal water content

BACKGROUND

Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as lower cholesterol. Although present in many foods, most trials have been in spreads or dairy products. Here we tested whether Bifidobacteria isolates could lower cholesterol, inhibit harmful enzyme activities, and control fecal water content.

METHODS

In vitro culture experiments were performed to evaluate the ability of Bifidobacterium spp. isolated from healthy Koreans (20 approximately 30 years old) to reduce cholesterol-levels in MRS broth containing polyoxyethanylcholesterol sebacate. Animal experiments were performed to investigate the effects on lowering cholesterol, inhibiting harmful enzyme activities, and controlling fecal water content. For animal studies, 0.2 ml of the selected strain cultures (108 approximately 109 CFU/ml) were orally administered to SD rats (fed a high-cholesterol diet) every day for 2 weeks.

RESULTS

B. longum SPM1207 reduced serum total cholesterol and LDL levels significantly (p < 0.05), and slightly increased serum HDL. B. longum SPM1207 also increased fecal LAB levels and fecal water content, and reduced body weight and harmful intestinal enzyme activities.

CONCLUSION

Daily consumption of B. longum SPM1207 can help in managing mild to moderate hypercholesterolemia, with potential to improve human health by helping to prevent colon cancer and constipation.

Effects of Lactobacillus plantarum MA2 isolated from Tibet kefir on lipid metabolism and intestinal microflora of rats fed on high-cholesterol diet

The objective of this study was to evaluate the effects of Lactobacillus plantarum MA2, an isolate from Chinese traditional Tibet kefir, on cholesterol-lowering and microflora of rat in vivo. Rats were fed on cholesterol-enriched experimental diet, supplemented with lyophilized L. plantarum MA2 powder, with a dose of 10(11) cells/day per mice. The results showed that L. plantarum MA2 feeding significantly lowered serum total cholesterol, low-density lipoprotein cholesterol, and triglycerides level, while there was no change in high-density lipoprotein cholesterol. In addition, liver total cholesterol and triglycerides was also decreased. However, fecal cholesterol and triglycerides was increased significantly (P < 0.05) in comparison with the control. Also, L. plantarum MA2 increased the population of lactic acid bacteria and bifidobacteria in the fecal, but it did not change the number of Escherichia coli as compared to control. Moreover, pH, moisture, and organic acids in the fecal were also measured. The present results indicate the probiotic potential of the L. plantarum MA2 strain in hypocholesterolemic effect and also increasing the probiotic count in the intestine.

The effects of Lactobacillus-fermented milk on lipid metabolism in hamsters fed on high-cholesterol diet

The objective of this study was to evaluate the effects of local Lactobacillus strains (NTU 101 and 102) on cholesterol-lowering effects in vivo. Thirty male hamsters were housed, divided into five groups, and fed on a cholesterol diet (5 g/kg diet) to induce hypercholesterolemia. Milk fermented by Lactobacillus paracasei subsp. paracasei NTU 101, Lactobacillus plantarum NTU 102, and Lactobacillus acidophilus BCRC 17010 was administrated for this study. After treatment with different fermented milk, blood was taken and liver was removed for the determination of lipoproteins, including total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride. Lactobacilli and bifidobacteria decreased (10(5)) in the control group; when hamsters were fed on fermented milk, the number of lactobacilli (10(7)-10(8)) and bifidobacteria (10(5)-10(7)) was increased. Serum and liver total cholesterol levels were significantly reduced by about 26.4, 23.5, and 30.1% and by about 17.7, 15.9, and 13.4% when hamsters were given fermented milk. However, serum HDL-C and LDL-C were also reduced. The results of this study showed that the hypocholesterolemic effect of local Lactobacillus strains was attributed to its ability to lower serum and liver total cholesterol levels. Thus, local Lactobacillus strains could significantly increase probiotic count.

Effect of Lactobacillus delbrueckii on cholesterol metabolism in germ-free mice and on atherogenesis in apolipoprotein E knock-out mice

Elevated blood cholesterol is an important risk factor associated with atherosclerosis and coronary heart disease. Several studies have reported a decrease in serum cholesterol during the consumption of large doses of fermented dairy products or lactobacillus strains. The proposed mechanism for this effect is the removal or assimilation of intestinal cholesterol by the bacteria, reducing cholesterol absorption. Although this effect was demonstrated in vitro, its relevance in vivo is still controversial. Furthermore, few studies have investigated the role of lactobacilli in atherogenesis. The aim of the present study was to determine the effect of Lactobacillus delbrueckii on cholesterol metabolism in germ-free mice and the possible hypocholesterolemic and antiatherogenic action of these bacteria using atherosclerosis-prone apolipoprotein E (apo E) knock-out (KO) mice. For this purpose, Swiss/NIH germ-free mice were monoassociated with L. delbrueckii and fed a hypercholesterolemic diet for four weeks. In addition, apo E KO mice were fed a normal chow diet and treated with L. delbrueckii for 6 weeks. There was a reduction in cholesterol excretion in germ-free mice, which was not associated with changes in blood or liver cholesterol concentration. In apo E KO mice, no effect of L. delbrueckii was detected in blood, liver or fecal cholesterol. The atherosclerotic lesion in the aorta was also similar in mice receiving or not these bacteria. In conclusion, these results suggest that, although L. delbrueckii treatment was able to reduce cholesterol excretion in germ-free mice, no hypocholesterolemic or antiatherogenic effect was observed in apo E KO mice.

Effect of probiotic supplementation on laying hen diets on yield performance and serum and egg yolk cholesterol

The effects of dietary supplementation of a commercial probiotic (BioPlus 2B) on daily feed consumption, egg yield, egg weight, specific gravity, body weight, feed conversion ratio, serum and egg yolk cholesterol, and serum trigylceride in layer hens were investigated. In 12 replicates, 480 27-week-old Brown-Nick layers were fed with diets containing 0, 250, 500 or 750 mg kg(-1) probiotic for 90 days. When compared with the controls, supplementation of 250, 500 and 750 mg kg(-1) probiotic increased egg production, but decreased the damaged egg ratio (p < 0.05), egg yolk cholesterol and serum cholesterol (p < 0.001) levels. In addition, serum triglyceride levels were reduced by using 500 and 750 mg kg(-1) probiotic supplementation (p < 0.001). Feed conversion ratios were positively affected by supplementation of 250 and 500 mg kg(-1) probiotic compared with controls (p < 0.05). There was no statistically significant difference between the control and all treatment groups on feed consumption, egg weight, specific gravity, body weight, and egg yolk weight.

Kefir consumption does not alter plasma lipid levels or cholesterol fractional synthesis rates relative to milk in hyperlipidemic men: a randomized controlled trial [ISRCTN10820810]

BACKGROUND

Fermented milk products have been shown to affect serum cholesterol concentrations in humans. Kefir, a fermented milk product, has been traditionally consumed for its potential health benefits but has to date not been studied for its hypocholesterolemic properties.

METHODS

Thirteen healthy mildly hypercholesterolemic male subjects consumed a dairy supplement in randomized crossover trial for 2 periods of 4 wk each. Subjects were blinded to the dairy supplement consumed. Blood samples were collected at baseline and after 4 wk of supplementation for measurement of plasma total, low-density lipoprotein, and high-density lipoprotein cholesterol and triglyceride concentrations, as well as fatty acid profile and cholesterol synthesis rate. Fecal samples were collected at baseline and after 2 and 4 wk of supplementation for determination of fecal short chain fatty acid level and bacterial content.

RESULTS

Kefir had no effect on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglyceride concentrations nor on cholesterol fractional synthesis rates after 4 wk of supplementation. No significant change on plasma fatty acid levels was observed with diet. However, both kefir and milk increased (p < 0.05) fecal isobutyric, isovaleric and propionic acids as well as the total amount of fecal short chain fatty acids. Kefir supplementation resulted in increased fecal bacterial content in the majority of the subjects.

CONCLUSIONS

Since kefir consumption did not result in lowered plasma lipid concentrations, the results of this study do not support consumption of kefir as a cholesterol-lowering agent.

Consumption of fermented and nonfermented dairy products: effects on cholesterol concentrations and metabolism

The objective of this article was to review existing literature concerning the effects and mechanisms of action of fermented dairy products on serum cholesterol concentrations. Although not without exception, existing evidence from animal and human studies suggests a moderate cholesterol-lowering action of fermented dairy products. Mechanistically, fermented milk has been shown to cause an increase in human gut bacterial content. These bacteria, once resident in the large intestine, are believed to ferment food-derived indigestible carbohydrates. Such fermentation causes increased production of short-chain fatty acids, which decreases circulatory cholesterol concentrations either by inhibiting hepatic cholesterol synthesis or by redistributing cholesterol from plasma to the liver. Furthermore, increased bacterial activity in the large intestine results in enhanced bile acid deconjugation. Deconjugated bile acids are not well absorbed by the gut mucosa and are excreted. Consequently, cholesterol, being a precursor of bile acids, is utilized to a greater extent for de novo bile acid synthesis. These actions combined are proposed as contributing mechanisms to the association of fermented milk consumption with decreased circulating cholesterol concentrations.

Effect of Lactobacillus reuteri on the prevention of hypercholesterolemia in mice

Administration of Lactobacillus reuteri CRL 1098 (10(4) cells/d) to mice for 7 d before inducing hypercholesterolemia (by feeding mice with a fat-enriched diet for the subsequent 7 d) was evaluated. At this low dose, L. reuteri was effective in preventing hypercholesterolemia in mice, producing a 17% increase in the ratio of high-density lipoprotein to low-density lipoprotein. Total cholesterol and triglycerides decreased by 22 and 33%, respectively, in the group that was not fed the lactobacilli. The hypocholesterolemic effect produced by L. reuteri CRL 1098 might be considered as indirect evidence of the permanency of the lactobacilli in the gut.

Effect of administration of fermented milk containing whey protein concentrate to rats and healthy men on serum lipids and blood pressure

The effect of fermented milk supplemented with whey protein concentrate on the serum lipid level of rats was investigated. The serum total cholesterol level for the group fed fermented milk with both Lactobacillus casei TMC0409 and Streptococcus thermophilus TMC 1543 was significantly lower than that of the control group (P<0.05) in rats. Furthermore, the effect of the longterm intake of this fermented milk on the serum lipid level of twenty healthy adult men was investigated. During the 8-wk study, the volunteers consumed 200 ml of fermented milk or placebo in the morning and evening. Blood samples were drawn for analysis three times, just before taking the experimental diet, and after 4 wk and 8 wk of consumption. After 8 wk, the high density lipoprotein cholesterol level for the fermented milk group showed a significant rise after 4 wk (P<0.05), whereas that of the placebo group showed no change even after 4 wk (P>0.05). The triglyceride level for the fermented milk group lowered significantly after 4 wk (<0.05), whereas that of the placebo group showed no change even after 4 wk (P>0.05). The atherogenic index [(total cholesterol - high density lipoprotein cholesterol)/high-density lipoprotein cholesterol] for the fermented milk group decreased significantly from 4.24 to 3.52 (P<0.05). The systolic blood pressure lowered significantly by the intake of fermented milk (P<0.05) On the other hand, such effect was not observed in the placebo group (P>0.05). These results indicate potential of the development of fermented milk with multiple therapeutic effects.

Effect of fermented milk (yogurt) containing Lactobacillus acidophilus L1 on serum cholesterol in hypercholesterolemic humans

OBJECTIVE

Two controlled clinical studies were performed to examine effects of consumption of one daily serving of fermented milk (FM) (yogurt) on serum lipids.

METHODS

In the first study, subjects were randomly allocated to FM containing Lactobacillus acidophilus L1 of human origin or to FM containing L. acidophilus ATCC 43211 of swine origin. In this single-blind study, subjects consumed one 200 ml serving of FM daily for 3 weeks. The second study was a double-blind, placebo-controlled, cross-over study. Subjects completed a 4-week first treatment, had a 2-week washout, and completed a second 4-week treatment. In the second study subjects consumed FM containing L. acidophilus L1 or placebo FM over 4 weeks.

RESULTS

In the first study, FM containing L. acidophilus L1 was accompanied by a 2.4% (p<0.05) reduction of serum cholesterol concentration. In the second study, strain L1 reduced serum cholesterol concentration by 3.2% (p<0.05) in the first treatment period. In the second treatment period there were no significant changes in serum cholesterol concentration. Combined analysis of the two L1 treatment studies demonstrated a 2.9% (p<0.01) reduction in serum cholesterol concentration.

CONCLUSION

Since every 1% reduction in serum cholesterol concentration is associated with an estimated 2% to 3% reduction in risk for coronary heart disease, regular intake of FM containing an appropriate strain of L. acidophilus has the potential of reducing risk for coronary heart disease by 6 to 10%.

Evidence for hypocholesterolemic effect of Lactobacillus reuteri in hypercholesterolemic mice

Swiss Albino mice were fed a diet enriched with fat to produce hypercholesterolemia. The further administration of Lactobacillus reuteri CRL 1098 (10(4) cells/d) to hypercholesterolemic mice for 7 d decreased total cholesterol by 38%, producing serum cholesterol concentrations similar to that of the control group (67.4 mg/ml). This low dose of L. reuteri caused a 40% reduction in triglycerides and a 20% increase in the ratio of high density lipoprotein to low density lipoprotein without bacterial translocation of the native microflora into the spleen and liver. These data suggest that L. reuteri CRL 1098 is an effective hypocholesterolemic adjuvant at a low cell concentration for mice.

Characterisation and selection of probiotic lactobacilli for a preliminary minipig feeding trial and their effect on serum cholesterol levels, faeces pH and faeces moisture content

Three out of 297 Lactobacillus strains isolated from pig faeces were selected for a feeding trial on account of their high bile-salt hydrolase (BSH) activity, bile-salt resistance, low pH tolerance and the production of antimicrobial substances. Two strains were identified as Lactobacillus johnsonii and one as Lactobacillus reuteri by DNA-DNA hybridisation. L. johnsoniii BFE 1061 produced a bacteriocin active against a range of lactic acid bacteria (LAB) and nonrelated bacteria including Clostridium perfringens. Six minipigs were maintained on a high-fat, high-cholesterol ('Western Style') diet for 17 weeks after which the diet was supplemented with the 'probiotic mixture' containing the above mentioned three Lactobacillus strains at 2 x 10(12) CFU per pig per day for five weeks. The mixture was given as a resuspended lyophilisate. During a two week follow-up period the minipigs received only the 'Western-style' diet without probiotic supplementation. A lowering effect on serum cholesterol levels was indicated after three weeks probiotic feeding, concomitant with an increase in the moisture content of the faeces and Lactobacillus cell numbers. Triglycerides, pH and number of lactic acid bacteria in faeces were not significantly influenced by probiotic supplementation.

Influence of yogurt and acidophilus yogurt on serum cholesterol levels in mice

The effects of yogurt and acidophilus yogurt on the weight gain, serum cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides, and the numbers of fecal lactobacilli and coliforms were investigated in mice assigned to three dietary treatments for 56 d: 1) commercial rodent chow and water (control), 2) commercial rodent chow and yogurt made from milk inoculated with a 3% (vol/vol) liquid culture of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus (yogurt), and 3) commercial rodent chow plus yogurt made from milk inoculated with a 0.01% (wt/vol) freeze-dried culture of Streptococcus thermophilus plus Lactobacillus acidophilus. The weight gains of mice receiving yogurt or acidophilus yogurt were higher than those of the mice in the control group. The mean values for serum cholesterol concentrations and LDL cholesterol concentrations were significantly decreased when acidophilus yogurt was fed on d 28 and 56. High density lipoprotein cholesterol and triglycerides were not affected by yogurt or acidophilus yogurt. The highest number of fecal lactobacilli was found in mice receiving acidophilus yogurt, and the number of fecal coliforms of that group was also lower than in the other two groups.

Effect of probiotic supplementation on growth, nitrogen utilisation and serum cholesterol in broilers

1. The effect of dietary probiotic supplementation on the growth, nitrogen utilisation and serum cholesterol content of broiler chickens was studied in 2 trials. 2. In experiment 1, the birds receiving the 0, 75, 100, 125 mg probiotic/kg diets had weight gains of 1204.0, 1272.0, 1268.3 and 1210.5, respectively at the end of 8 weeks of feeding. The group of birds fed on the 75 mg probiotic supplemented diet retained significantly (P < 0.01) more nitrogen than the control birds. Serum cholesterol content was lower in the probiotic-supplemented birds (93.3 mg/100 ml) compared to the control birds (132.2 mg/100 ml). 3. In the second experiment the probiotic plus antibiotic-supplemented group of birds had the maximum weight gain (1148.5 g) followed by antibiotic (1141.3 g), probiotic-supplemented (1128.4 g) and control birds (1045.6 g) after 6 weeks. Nitrogen retention was greatest in the antibiotic--(48.5%) followed by the probiotic--(46.5%), probiotic plus antibiotic-supplemented groups (46.3%) compared to 40.2% in control birds. 4. The apparent metabolisable energy was greatest in birds receiving the probiotic plus antibiotic-supplemented diet (12.37 MJ/kg) followed by antibiotic--(12.00 MJ/kg), probiotic-supplemented birds (11.92 MJ/kg) than in control birds (11.62 MJ/kg). Serum cholesterol was significantly (P < 0.01) lower in probiotic-supplemented birds (86.1 mg/dl) compared to 118.4 mg/dl in control birds.

Effect of probiotic supplementation on serum/yolk cholesterol and on egg shell thickness in layers

1. The effect of probiotic supplementation on egg production, on serum and yolk cholesterol and on egg shell thickness in 24 White Leghorn layers was studied from 28-38 weeks of age. 2. In 3 treatments the diet was supplemented with 0, 100 and 150 mg probiotic/kg food. 3. In the 100 mg probiotic group, egg production improved by 5%, and shell thickness improved slightly, with fewer thin-shelled eggs than in the control (8.6% compared to 18.6%). 4. The initial serum cholesterol concentration of 170.2 mg/dl in control birds remained similar throughout the 10-week experimental period, whereas in the 150 mg group the initial value of 176.5 mg/dl decreased to 114.3 mg by week 10. 5. Yolk cholesterol concentration was 14.69 mg in the control group and 11.28 and 11.37 mg/g in the 100 and 150 mg probiotic groups respectively. Overall mean total egg cholesterol was thus reduced by probiotic supplementation.

Anticarcinogenic, hypocholesterolemic, and antagonistic activities of Lactobacillus acidophilus

Lactobacillus acidophilus is considered to possess health-promoting attributes. These include anticarcinogenic and hypocholesterolemic properties and antagonistic action against intestinal and food-born pathogens. L. acidophilus can also survive the hostile environment and establish in the complex ecosystem of the gastrointestinal tract. Therefore, the beneficial effects of ingesting L. acidophilus accrue over a longer period than those organisms that cannot colonize the gut. However, the exact mechanisms of these attributes are not known. Presumably, the anticarcinogenic activity may be attributed to production of compounds and/or conditions that inhibit the proliferation of tumor cells, suppression of microorganisms that convert procarcinogens to carcinogens, and degradation of carcinogens formed. They hypocholesterolemic effect is probably exerted by inhibition of 3-hydroxy-3-methylglutaryl CoA reductase, which is a rate-limiting enzyme in endogenous cholesterol biosynthesis in the body and by promoting the excretion of dietary cholesterol in feces as a result of coprecipitation in the presence of deconjugated bile acids in the intestine and/or adsorption by the organisms. The antagonistic effect against pathogens and other organisms is possibly mediated by competition for nutrients and adhesion sites, formation of metabolites such as organic acids, hydrogen peroxide, and production of antibiotic-like compounds and bacteriocins.

Effects of skim milk, skim milk yogurt, orotic acid, and uric acid on lipid metabolism in rats

The effects of feeding two milk products (skim milk and skim milk yogurt) and two proposed hypocholesterolemic factors (orotic acid and uric acid) on serum cholesterol (HDL, LDL, total, HDL/Total and HDL/LDL), liver lipids (total liver lipids and liver cholesterol), and aortal cholesterol were studied. Ten groups, of nine rats each, were fed isocaloric Chow-based diets containing water, 45% skim milk (SM), 45% skim milk yogurt (SMY), and 0.0025% orotic acid (OA) or 0.001% uric acid (UA), without or with cholesterol. The SM diet (with cholesterol) resulted not only in lower total cholesterol (P < 0.10), LDL cholesterol (P < 0.05), aortal cholesterol (P < 0.01), and liver cholesterol (P < 0.10), but also in increased HDL (P < 0.05) and HDL/LDL (P < 0.10) cholesterol ratio. The SMY diet, on the other hand, resulted in lowered total serum cholesterol (P < 0.05) and aortal cholesterol (P < 0.01) and in higher LDL (P < 0.05) cholesterol. The hypocholesterolemic effects were more marked for SM than for SMY. Addition of OA and UA to diets increased serum cholesterol, LDL cholesterol, and total liver lipids; the OA diet also increased liver cholesterol. Neither OA nor UA alone was the factor responsible for the hypocholesterolemic effects seen with SM and SMY feeding.

Lactic acid bacteria and human health

Although claims for health and nutritional benefits have been made for lactic acid bacteria in fermented dairy products for nearly a century, the nutritional and therapeutic value of these organisms is still controversial. This article will review the scientific basis of these claims. There are numerous studies showing fermentation of food with lactobacilli increase the quantity, availability, digestibility, and assimilability of nutrients. The basis for this conclusion comes from direct measurements of vitamin synthesis and from increased feed efficiency when fermented products are fed to animals. There have been a number of studies showing that various fermented dairy products lower serum cholesterol levels in humans and animals. These studies are reviewed and the validity of these findings are assessed. A summary of the evidence indicating that lactase deficient individuals can eat yogurt and the mechanisms involved in this toleration is reviewed. The role of fermented dairy products in inhibiting tumor growth and chemically induced tumors in animals is discussed and the possible mechanisms involved in this protective effect are reviewed. Fermented dairy products and lypholized lactobacilli preparations have been shown to be useful in treating and preventing various intestinal infections including; salmonellosis, shigellosis and antibiotic induced diarrhea. In this context a specific lactobacillus designated GG has been shown to be useful in treating recurring diarrhea caused by a toxin produced by Clostridium difficile.

Assimilation of cholesterol by Lactobacillus acidophilus

Considerable variation was found among strains of Lactobacillus acidophilus isolated from the fecal flora of pigs with regard to the ability to grow well in the presence of bile and to assimilate cholesterol from a laboratory growth medium. The uptake of cholesterol occurred only when the culture(s) was growing in the presence of bile under anaerobic conditions. Consumption of L. acidophilus RP32, which was selected for its ability to grow well in the presence of bile and to assimilate cholesterol from the laboratory medium, significantly inhibited increases in serum cholesterol levels of pigs (P less than 0.05) fed a high-cholesterol diet. Consumption of L. acidophilus P47, which was selected for its ability to grow in the presence of bile and lack of ability to remove cholesterol from the growth medium, failed to have a similar effect. This indicates that certain strains of L. acidophilus act directly on cholesterol in the gastrointestinal tract, and thus may be beneficial in reducing serum cholesterol levels.