Comparing effects of carbohydrate (CHO) blockers and trivalent chromium on CHO-induced insulin resistance and elevated blood pressure in rats.

OBJECTIVE: In Sprague-Dawley rats (SD), we compared two categories of natural dietary supplements that influence carbohydrate (CHO) metabolism via different basic mechanisms to ameliorate insulin resistance (IR) and elevated blood pressure (BP) associated with heavy sugar/starch consumption. Two dietary supplements (bean extract and l-arabinose) are often referred to as carb blockers (CBs), because they slow the gastrointestinal absorption of CHO. Trivalent chromium (CR) falls into a group of so-called insulin sensitizers, because its major effect is to enhance peripheral insulin sensitivity. METHOD: We divided 48 mature male SD into 4 groups of 12. The first group received powdered baseline diet alone (Con). The remaining 3 SD groups (groups 2-4) ingested regular rat chow containing 20% w/w sucrose and 20% w/w rice starch. The second group received only this CHO-enriched chow. To the high-CHO diets of the remaining two groups, either CB to slow CHO absorption (CHO + CB) (group 3) or an insulin sensitizer, trivalent CR (CHO + CR; group 4), was added. RESULTS: Compared to Con group 1, adding high CHO content to the diet of group 2 significantly increased circulating glucose levels and systolic BP (SBP). Addition of CB or CR to the feed of groups 3 and 4 overcame the perturbations that occurred with high CHO challenge in group 2; that is, they lowered circulating glucose concentrations to Con levels, enhanced response to exogenous insulin, and overcame the gradual elevation of SBP. Compared to group 2, the two treatment groups (3 and 4) also showed decreased renin-angiotensin system activity, decreased serum angiotensin-converting enzyme activity, and enhanced nitric oxide activity. CONCLUSIONS: Our data indicate that high doses of CB and CR, despite their different mechanisms of action, can completely overcome CHO-induced IR and BP elevations. The data further suggest that CB and CR affect only the changes brought on by heavy CHO ingestion, because IR and SBP in groups 3 and 4 mirrored Con values (group 1), never producing values lower than baseline. Earlier use of CB and CR in the life cycle appears more effective in overcoming CHO-induced perturbations than later use.

In vitro and in vivo effects of two coconut oils in comparison to monolaurin on Staphylococcus aureus: rodent studies.

Since monolaurin, a monoglyceride formed in the human body in small quantities, has proven effective both in vitro and in vivo against certain strains of Staphylococcus aureus, an important question arises whether consuming a substance high in lauric acid content, such as coconut oil could increase intrinsic monolaurin production to levels that would be successful in overcoming staphylococcal and other microbial invaders. Both a cup plate method and a microdilution broth culture system were employed to test bacteriostatic and bactericidal effects of the test agents in vitro. To test effectiveness in vivo, female C3H/he mice (10-12 per group) were orally administered sterile saline (regular control), vancomycin (positive control), aqueous monolaurin, or two varieties of coconut oil (refined, bleached, deodorized coconut oil and virgin coconut oil) for 1 week before bacterial challenge and 30 days after. A final group received both monolaurin and vancomycin. In contrast to monolaurin, the coconut oils did not show bactericidal activity in vitro. In vivo, the groups receiving vancomycin, monolaurin, or the combination showed some protection--50-70% survival, whereas the protection from the coconut oils were virtually the same as control--0-16% survival. Although we did not find that the two coconut oils are helpful to overcome S. aureus infections, we corroborated earlier studies showing the ability of monolaurin to do such.

Fraction SX of maitake mushroom favorably influences blood glucose levels and blood pressure in streptozotocin-induced diabetic rats.

We assessed whether fraction SX derived from maitake mushroom could play a beneficial role in the treatment of a laboratory model of type-1 diabetes by decreasing circulating glucose levels and lowering blood pressure (BP). We injected 50 mg/kg body weight (BW) streptozotocin (STZ) intraperitoneally (i.p.) into 48 male Sprague-Dawley rats (SD) to produce a laboratory model of type-1 diabetes. SD were divided into four groups of 12 SD. A control group ate straight pulverized rat chow. To three treatment groups, we added into the pulverized rat chow: gliclazide (10 mg/kg), pioglitazone (10-30 mg/kg), or maitake SX (2.5 g/kg). In addition to measuring BW, circulating glucose level, and BP, the following procedures were also carried out: insulin challenge (insulin sensitivity), losartan challenge (renin-angiotensin system activity), Nw-nitro-L arginine-methyl ester hydrochloride (LNAME) challenge (nitric oxide [NO] system activity), and evaluation of serum angiotensin converting enzyme (ACE) activity. All treatments compared with control generally decreased circulating glucose levels, but only the maitake SX consistently enhanced measured insulin sensitivity. We found that maitake SX could significantly lower systolic blood pressure (SBP) in diabetic SD. In general, only SD receiving maitake SX, not the two drugs, showed decreased activity of the renin-angiotensin system and increased NO system activity compared with control under the conditions examined. Our results suggest that maitake SX may be useful for treating perturbations in glucose-insulin metabolism and elevated BP in type-1 diabetes.

Niacin-bound chromium increases life span in Zucker Fatty Rats.

Avoiding insulin resistance (IR) associated with aging might lengthen life span based on previous studies using caloric-restricted animals. We assessed whether consuming niacin-bound chromium (NBC) alone or in a formula containing other so-called "insulin sensitizers" would overcome various manifestations of aging and extend life span in Zucker Fatty Rats (ZFR). We compared many metabolic parameters of ZFR fed NBC alone (n=12) or NBC in a unique formula (n=10) to a control group (n=10). In addition to NBC, the formula contained Allium sativum, Momordica charantia, Trigonella foenum-graecum and Gymnema sylvestre. The formula group received roughly 1/2 as much NBC daily as the NBC group. At week 44, all rats still lived, and no abnormalities in blood count (CBC), renal, or liver functions were found. In the two treatment groups compared to control, circulating glucose levels were significantly lower, with a trend toward lower HbA1C. Relatively elevated cholesterol and triglyceride concentrations occurred in the formula group. Compared to control, the NBC group had increased average lifespan (21.8%), median lifespan (14.1%), 30th percentile survival (19.6%), and maximum lifespan (22%). Despite similar beneficial effects on the glucose and blood pressure systems, a difference in aging was also found when the NBC group was compared to the formula group. When all rats in the other two groups had died, four in the NBC group continued to live at least a month longer. We attribute lack of a similar aging effect in the formula group to either lower dosing of NBC and/or that various ingredients in the formula counteracted the antiaging effect(s) of NBC.

High dose astaxanthin lowers blood pressure and increases insulin sensitivity in rats: are these effects interdependent?

The present investigation in Sprague-Dawley rats (SD) was designed to examine effects of astaxanthin (Asta) at different doses on elevated blood pressure (BP) and glucose-insulin perturbations produced by heavy sucrose ingestion. We also examined effects of Asta on BP during restraint stress. SD were divided into six groups each containing eight rats. All SD ate a basic diet of ground regular rat chow with sucrose added at 30% w/w. The Control group received only the basic diet containing added sucrose, while the other five groups each received the same diet with added test material: captopril, (30 mg/Kg), pioglitazone (15.0 mg/Kg), low Asta (25 mg/Kg), medium Asta (50 mg/kg) or high Asta (100 mg/Kg). Many tests were carried out to examine the mechanisms behind the effects of Asta on BP (serum ACE activity, losartan challenge, and LNAME challenge) and the glucose-insulin system (glucose tolerance, HOMA measurement, and insulin challenge). In SD, a relatively low dose of Asta decreased SBP, but produced no major changes in the glucose-insulin system simulating results from a previous study using Zucker Fatty Rats. Increasing the dose of Asta resulted in both a lowering of elevated systolic BP and enhanced insulin sensitivity determined by many different estimations. BP lowering was consistent with changes in the renin-angiotensin (RAS) and nitric oxide (NO) systems. At the examined doses of each, captopril lowered BP in SD without influencing glucose-insulin metabolism, whereas pioglitazone favorably affected glucose-insulin metabolism while showing essentially no effects on BP. Accordingly, Asta beneficially affects both sucrose-induced elevations of BP and insulin resistance at relatively high doses in SD. Also, Asta at higher doses lessens restraint stress, whereas, captopril and pioglitazone did not at the doses examined, even though they influenced the BP and glucose-insulin systems respectively.

Maitake mushroom extracts ameliorate progressive hypertension and other chronic metabolic perturbations in aging female rats.

OBJECTIVE: We assessed the ability of two commercially-available fractions labeled SX and D derived from the edible maitake mushroom to overcome many age-associated metabolic perturbations such as progressive, age-related elevation of blood pressure, over activity of the renin-angiotensin system (RAS), decreased insulin sensitivity, and inflammation in an in vivo laboratory model. DESIGN AND METHOD: We divided forty mature, female Sprague-Dawley rats (SD) into five groups of eight. SD ingested regular rat chow containing added sucrose (20% w/w). The groups received baseline diet alone (control) or baseline diet containing captopril, niacin-bound chromium, maitake fraction SX, or maitake fraction D. In addition to blood pressure readings, the following procedures were implemented: losartan and insulin challenges, evaluation of serum ACE activity, glucose tolerance testing, blood chemistries, LNAME challenge, and measurement of various circulating cytokines. RESULTS: We found that implementation of all test conditions stopped the gradual elevation of systolic blood pressure (SBP) in the SD over the four months of study, even reversing some of the previous elevation that occurred over time. In general, the treatment groups showed decreased activity of the RAS estimated by less lowering of SBP after losartan challenge and decreased serum ACE activity and were more sensitive to exogenous insulin challenge. TNFa levels decreased in all four test groups suggesting a lessening of the inflammatory state. CONCLUSIONS: We believe our data suggest that maitake mushroom fractions lessen age-related hypertension, at least in part, via effects on the RAS; enhance insulin sensitivity; and reduce some aspects of inflammation--actions that should lead to a longer, healthier life span.

Influence of gel and powdered formulations of coenzyme Q10 on metabolic parameters in rats.

The healthful benefits of two commercially available formulations of coenzyme Q10 (Co Q10), one in gel and the other in a powdered form, on a variety of metabolic parameters in Sprague-Dawley rats (SD) were compared to control. The principal metabolic parameters examined were systolic blood pressure (SBP), DNA fragmentation, and free radical formation in hepatic and renal tissues. Compared to control, the powdered formulation significantly decreased SBP in the normotensive SD, whereas both commercial formulations lowered hepatic and renal DNA fragmentation and free radical formation. The gel-formulation lowered hepatic DNA fragmentation more than the powdered-formulation. In conclusion, both gel- and powdered-formulations of Co Q10 significantly influenced the metabolic parameters assessed in a favorable fashion, with the powdered-formulation more effective on SBP and the gel-formulation more effective on overcoming hepatic DNA fragmentation. From the data, we conclude that the choice of the formulation containing Co Q10 to be used should be based on the desired healthful benefits.

Comparing metabolic effects of six different commercial trivalent chromium compounds.

Recent reports provide cogent evidence that the average individual becomes chromium deficient with age. Unfortunately, chromium deficiency is strongly associated with many aspects of the Metabolic Syndrome, including insulin resistance and type 2 diabetes. Since replacement of chromium, per os, often ameliorates many deleterious manifestations associated with insulin resistance and diabetes, it is not surprising that many different, commercial trivalent chromium compounds are available on the market. However, previous reports have shown that the form of trivalent chromium (negative charges) can influence effectiveness markedly. We compared various commercial forms of trivalent chromium commonly used alone or in formulations, to examine whether they are equally effective and non-toxic. In the first study, five different chromium products were examined - citrate, amino acid chelate (AAC), chelavite, polynicotinate (NBC), and nicotinate. In the second study, effects of NBC and picolinate were assessed. Results demonstrated that only chelavite and NBC improved insulin sensitivity, and only NBC decreased systolic blood pressure (SBP) significantly. In the second study, both picolinate and NBC significantly decreased SBP compared to control. NBC and picolinate decreased malonyldialdehyde concentrations (free radical formation) and DNA fragmentation in hepatic and renal tissues. No evidence of adverse effects was noted with any of the compounds tested. In conclusion, while all the trivalent chromium compounds tested seem safe, only three enhanced insulin sensitivity (NBC, chelavite, and picolinate) and only two decreased SBP significantly (NBC and picolinate). Furthermore, both NBC and picolinate were protective in lessening free radical formation and DNA damage in the liver and kidneys.

Blood pressure lowering effects of niacin-bound chromium(III) (NBC) in sucrose-fed rats: renin-angiotensin system.

Excessive intake of sugars significantly elevates systolic blood pressure (SBP) in susceptible rats. Although the exact pathological mechanisms behind sugar-induced hypertension are uncertain and may be multiple, disturbances in the renin-angiotensin system (RAS) manifested by elevated circulating levels of angiotensin-2 may be involved. We attempted to confirm that the RAS was significantly involved in sugar-induced BP elevations and examined whether the ability of niacin-bound chromium (NBC) to ameliorate sugar-induced SBP elevations was due, at least in part, through effects on the RAS. Initially, 40 mature Sprague-Dawley rats (SD), male and female, were involved in the study comparing two methods to estimate rat blood pressure indirectly. Then 13 were selected to examine the effects of NBC on the RAS. All rats eventually ingested a diet heavy in sucrose (30%w/w). In addition to blood pressure readings, the following procedures were implemented: insulin and losartan challenges, evaluation of serum ACE activity, measurement of serum angiotensin-2 levels, blood chemistries, and LNAME challenge. While dietary sucrose raised SBP significantly in control, adding NBC to the treatment group lowered it back toward baseline. The treatment group was more sensitive to exogenous insulin challenge and showed decreased activity of the RAS estimated by less lowering of SBP after losartan challenge, decreased serum ACE (angiotensin-converting enzyme) activity, and lower levels of circulating angiotensin-2. The former two parameters showed statistical significance; and the latter, a trend toward statistical significance. A separate group receiving captopril served as a positive control and showed decreased ACE activity and circulating levels of angiotensin-2 compared to the control group. Our data suggest that the RAS plays a significant role in sugar-induced hypertension and that NBC lowers SBP, at least in part, via actions on the RAS. Other findings suggest that the NO system is important in sucrose-induced BP elevations as well.

Inhibition by natural dietary substances of gastrointestinal absorption of starch and sucrose in rats and pigs: 1. Acute studies.

Rapid gastrointestinal absorption of refined carbohydrates (CHO) is linked to perturbed glucose-insulin metabolism that is, in turn, associated with many chronic health disorders. We assessed the ability of various natural substances, commonly referred to as "CHO blockers," to influence starch and sucrose absorption in vivo in ninety-six rats and two pigs. These natural enzyme inhibitors of amylase/sucrase reportedly lessen breakdown of starches and sucrose in the gastrointestinal tract, limiting their absorption. To estimate absorption, groups of nine SD rats were gavaged with water or water plus rice starch and/or sucrose; and circulating glucose was measured at timed intervals thereafter. For each variation in the protocol a total of at least nine different rats were studied with an equal number of internal controls on three different occasions. The pigs rapidly drank CHO and inhibitors in their drinking water. In rats, glucose elevations above baseline over four hours following rice starch challenge as estimated by area-under-curve (AUC) were 40%, 27%, and 85% of their internal control after ingesting bean extract, hibiscus extract, and l-arabinose respectively in addition to the rice starch. The former two were significantly different from control. L-Arabinose virtually eliminated the rising circulating glucose levels after sucrose challenge, whereas hibiscus and bean extracts were associated with lesser decreases than l-arabinose that were still significantly lower than control. The glucose elevations above baseline over four hours in rats receiving sucrose (AUC) were 51%, 43% and 2% of control for bean extract, hibiscus extract, and L-arabinose, respectively. Evidence for dose-response of bean and hibiscus extracts is reported. Giving the natural substances minus CHO challenge caused no significant changes in circulating glucose concentrations, indicating no major effects on overall metabolism. A formula combining these natural products significantly decreased both starch and sucrose absorption, even when the CHO were given simultaneously. These results support the hypothesis that the enzyme inhibitors examined here at reasonable doses can safely lower the glycemic loads starch and sucrose.

Inhibition by natural dietary substances of gastrointestinal absorption of starch and sucrose in rats 2. Subchronic studies.

Acute oral consumption of various natural inhibitors of amylase (bean and hibiscus extracts) and sucrase (L-arabinose) reduce absorption of starch and sucrose respectively in rats and pigs measured by lessened appearance of circulating glucose levels. The present subchronic study was designed to determine whether these selected inhibitors of gastrointestinal starch and sucrose absorption (so-called "carb blockers") remain effective with continued use and to assess their metabolic influences after prolonged intake. Sprague-Dawley rats were gavaged twice daily over nine weeks with either water or an equal volume of water containing a formula that included bean and hibiscus extracts and L-arabinose. To estimate CHO absorption, control and treated Sprague-Dawley rats were gavaged with either water alone or an equal volume of water containing glucose, rice starch, sucrose, or combined rice starch and sucrose. Circulating glucose was measured at timed intervals over four hours. The ability to decrease starch and sucrose absorption use. No toxic effects (hepatic, renal, hematologic) were evident. Blood chemistries revealed significantly lower circulating glucose levels and a trend toward decreased HbA1C in the nondiabetic rats receiving the natural formulation compared to control. Subchronic administration of enzyme inhibitors was also associated with many metabolic changes including lowered systolic blood pressure and altered fluid-electrolyte balance. We postulate that proper intake of natural amylase and sucrase inhibitors may be useful in the prevention and treatment of many chronic disorders associated with perturbations in glucose-insulin homeostasis secondary to the rapid absorption of refined CHO.

Enhanced insulin-hypoglycemic activity in rats consuming a specific glycoprotein extracted from maitake mushroom.

AIM: Intraperitoneal glucose tolerance (ipGTT) and insulin challenge (ICT) tests were implemented to evaluate whether a specific glycoprotein extract of maitake mushroom (Grifola frondosa) known as SX-fraction enhances insulin sensitivity in spontaneously hypertensive rats (SHR). METHODS: SHR were divided randomly into a control group, a group receiving the antidiabetic drug, pioglitazone, in their diet, and three groups consuming three different concentrations of SX-Fraction derived from maitake mushroom in their food. The response of circulating glucose and insulin concentrations was examined at different time periods during an ipGTT. The major action of exogenous insulin during the ipGTT occurred within a 15-min period following injection of regular insulin. Accordingly, hypoglycemic activity was evaluated in SHR with and without glucose challenge over a short time frame in the ICT. RESULTS: Evidence gathered from the ipGTT and ICT tests suggests that the SX-fraction of Maitake in a proper dosage as well as pioglitazone enhance insulin sensitivity. Ingestion of SX-fraction produced a lower-circulating level of glucose after challenge despite no rise in circulating insulin. Compared to control, significantly lower-circulating glucose levels were seen in the groups consuming pioglitazone and higher doses of SX-fraction at 7.5 min after insulin challenge whether or not glucose was given concomitantly. CONCLUSION: SHR in the pioglitazone and SX-fraction groups showed improved glucose tolerance despite no elevation of circulating insulin concentrations and showed enhanced sensitivity to exogenous insulin. Thus, a glycoprotein extract from Maitake mushroom (SX-fraction) should be considered as an alternative method for improving insulin sensitivity.

Whole cinnamon and aqueous extracts ameliorate sucrose-induced blood pressure elevations in spontaneously hypertensive rats.

OBJECTIVE: Many agents (nutrients, nutraceuticals, and drugs) that enhance insulin sensitivity and/or reduce circulating insulin concentrations lower blood pressure (BP). Recently, it was reported that cinnamon has the potential to favorably influence the glucose/insulin system. Accordingly, the purpose of the present study was to examine the effects of dietary cinnamon on systolic BP (SBP), and various glucose- and insulin-related parameters in spontaneously hypertensive rats (SHR). METHODS: In a series of three experiments, treated SHR eating sucrose and non sucrose containing diets were given various amounts of cinnamon, cinnamon extracts, or chromium. Then various parameters such as: body weight, systolic blood pressure, hematology and blood chemistries were followed for three to four weeks. RESULTS: Diets high in sucrose content are associated with insulin resistance and the elevation of SBP. Addition to diets of cinnamon (8% w/w) reduced the SBP of rats eating sucrose containing diets to virtually the same levels as SHR consuming non sucrose containing (only starch) diets. The presence of cinnamon in the diet also decreased the SBP of SHR consuming a non sucrose-containing diet, suggesting that cinnamon reduces more than just sucrose-induced SBP elevations--perhaps a genetic component(s) of the elevated BP as well. The effects of cinnamon on SBP tended to be dose-dependent. Cinnamon did not decrease the levels of blood glucose, but did lower circulating insulin concentrations. Aqueous extracts of cinnamon also decreased SBP and lowered the circulating levels of fructosamine. CONCLUSIONS: Cinnamon is used for flavor and taste in food preparation, but cinnamon may have additional roles in glucose metabolism and BP regulation. Therefore, BP regulation may not only be influenced favorably by limiting the amounts of dietary substances that have negative effects on BP and insulin function but also by the addition of beneficial ones, such as cinnamon, that have positive effects.

Does 5-hydroxytryptophan cause acute and chronic toxic perturbations in rats?

In 1989, an epidemic of eosinophilia-myalgia syndrome (EMS) occurred in the United States that was attributed to contaminated l-tryptophan (LT). Features of tryptophan-induced EMS included debilitating myalgia and marked peripheral eosinophilia. Although the contaminant(s) was found only in the product produced by a single manufacturer (Showa Denko), all LT was withdrawn from the market and replaced by 5 hydroxytryptophan (5HTP). The belief was that the latter should not contain the implicated contaminant(s), because it was manufactured by a process entirely different from the banished LT. Nevertheless, in 1994 a case diagnosed as EMS appeared. Although the exact causative factor(s) in LT and the possible 5-HTP-induced EMS are uncertain, many reported finding "Peak E" in contaminated LT and the presence of "Peak X" in the 5-HTP of the 1994 case. The latter finding led some to assume that Peak X was a potential pathological agent in 5-HTP that might cause future cases of EMS. To determine whether 5-HTP could cause EMS, we followed 120 male Sprague-Dawley rats, 7 to 8 weeks of age (body weight 200-250 g), for 1 year. They were divided into three groups of 40. One group acted as control, drinking only water; a second group received a low dose of 5-HTP in their drinking water (87.5 mg/dL); and the last group drank a high dose of 5-HTP, 875 mg/dL. No significant differences in the body weights of these three groups of animals were observed over the year. After 2 months, systolic blood pressures (SBP) in the 5-HTP groups were significantly lower for the duration of the study. At the end of 12 months, SBP of the control group averaged 140 mm Hg, the low-dose 5-HTP group averaged 133 mm Hg, and the high-dose group averaged 125 mm Hg. Even though enough 5-HTP was given to cause a physiological response, no significant differences were found in the hematological values, including eosinophil count. Also, no significant differences were found in hepatic and renal values. In the histological studies, no treatment-related changes were noted in the hearts, livers, pancreases, leg striated muscles, and small intestines. In particular, there was no evidence of eosinophilic infiltration and fascial/perimysial inflammation. Accordingly, no significant evidence of EMS was seen in rats receiving high-dose 5-HTP for 1 year.

Minimum inhibitory concentrations of herbal essential oils and monolaurin for gram-positive and gram-negative bacteria.

New, safe antimicrobial agents are needed to prevent and overcome severe bacterial, viral, and fungal infections. Based on our previous experience and that of others, we postulated that herbal essential oils, such as those of origanum, and monolaurin offer such possibilities. We examined in vitro the cidal and/or static effects of oil of origanum, several other essential oils, and monolaurin on Staphylococcus aureus, Bacillus anthracis Sterne, Escherichia coli, Klebsiella pneumoniae, Helicobacter pylori, and Mycobacterium terrae. Origanum proved cidal to all tested organisms with the exception of B. anthracis Sterne in which it was static. Monolaurin was cidal to S. aureus and M. terrae but not to E. coli and K. pneumoniae. Unlike the other two gram-negative organisms, H. pylori were extremely sensitive to monolaurin. Similar to origanum, monolaurin was static to B. anthracis Sterne. Because of their longstanding safety record, origanum and/or monolaurin, alone or combined with antibiotics, might prove useful in the prevention and treatment of severe bacterial infections, especially those that are difficult to treat and/or are antibiotic resistant.

Effects of Essential Oils and Monolaurin on Staphylococcus aureus: In Vitro and In Vivo Studies.

The antimicrobial properties of volatile aromatic oils and medium-chain fatty acids derived from edible plants have been recognized since antiquity. To give examples, Origanum oil, used as a food-flavoring agent, possesses a broad spectrum of antimicrobial activity due, at least in part, to its high content of phenolic derivatives such as carvacrol and thymol. Similarly, lauric acid, present in heavy concentrations in coconuts, forms monolaurin in the body that can inhibit the growth of pathogenic microbes. Using Staphylococcus aureus in broth cultures and a microdilution method, comparative efficacy of Origanum oil, and a constituent carvacrol, other essential oils and monolaurin were examined. Origanum oil was the most potent of the essential oils tested and proved bactericidal in culture to two strains of Staphylococcus aureus (ATCC #14154 and #14775) at 0.25 mg/mL. In vitro, monolaurin's effects mirrored Origanum oil. The combination of both was bactericidal at the 0.125 mg/mL concentration of each. In two separate In vivo experiments, injected Staphylococcus aureus (ATCC #14775) killed all 14 untreated mice within a 1-week period. In treated mice, over one third survived for 30 days when given oral Origanum oil daily for 30 days (6/14). Fifty percent of the mice survived for 30 days when receiving daily vancomycin (7/14) and monolaurin (4/8). Over 60% of mice survived when receiving a daily combination of Origanum oil and monolaurin (5/8). Origanum oil and/or monolaurin may prove to be useful antimicrobial agents for prevention and therapy of Staphylococcus aureus infections.

Effects of niacin-bound chromium, Maitake mushroom fraction SX and (-)-hydroxycitric acid on the metabolic syndrome in aged diabetic Zucker fatty rats.

Previous studies in our laboratories have demonstrated that niacin-bound chromium (NBC), Maitake mushroom and (-)-hydroxycitric acid (HCA-SX) can ameliorate hypertension, dyslipidemias and diabetes mellitus, and therefore may be useful in weight management. In the present study, we used aged, diabetic Zucker fatty rats (ZFR) (70-75 weeks) in order to determine whether NBC, fraction SX of Maitake mushroom (MSX) and 60% (-)-hydroxycitric acid (HCA-SX) from Garcinia cambogia, alone or in combination, can affect certain aspects of the metabolic syndrome. Syndrome X or metabolic syndrome has been described as a concurrence of disturbed glucose and insulin metabolism, overweight and abdominal fat distribution, mild dyslipidemia, and hypertension, which are associated with subsequent development of type 2 diabetes mellitus and cardiovascular disease. Four groups of eight ZFR were gavaged daily with different supplements. For the initial three weeks, the control group of ZFR received only water, the second group received NBC 40 mcg elemental chromium/day, the third group received MSX 100 mg/day and the last group received HCA-SX 200 mg/day. During weeks 4-6, the doses of each treatment were doubled. The control animals lost approximately 50 g body weight (BW) per rat over 6 weeks of treatment, which is characteristic of these animals in declining health. In contrast, eight ZFR receiving NBC lost approximately 9 g BW per rat, while rats consuming MSX lost 16 g BW per rat. However, ZFR receiving HCA-SX simulated the pattern in the control group because these animals lost approximately 46 g BW per rat. The wide individual variations resulted in a lack of statistical significance among groups. Nevertheless, 75% of the ZFR in the control group lost more than 50 g BW over the 6 weeks duration, whereas none of the ZFR receiving NBC, 25% of the ZFR receiving MSX and 57% of the ZFR receiving HCA-SX lost over 50 g BW over the 6 weeks of the study. ZFR in all 3 treatment groups showed significantly lower blood pressures as compared to control, which seemed to be dose related. The general trend was for renal and liver blood parameters, hepatic and renal lipid peroxidation and DNA fragmentation to improve due to the supplementation of these natural products. Treatment of animals with a combination of these three novel supplements resulted in a lower SBP and maintenance of BW compared to control animals. These results demonstrate that elderly diabetics and even aging individuals might benefit from a similar regimen.

Comparison of Saw Palmetto (extract and whole berry) and Cernitin on prostate growth in rats.

Pharmaceuticals such as finasteride and alpha blockers are used to treat symptoms of benign prostatic hyperplasia (BPH) and are known to cause severe adverse reactions. Accordingly, a search for safer, natural products has been undertaken. Two natural agents (nutraceuticals) have come under recent scrutiny; because natural products, in general, often have evidence of long-term safety. The present study compares the in vivo effects on androgen-induced prostatic enlargement in rats of two nutraceuticals--the widely recognized Saw Palmetto (Serenoa repens) and the less well-known Cernitin (defined pollen extract). Non-castrated rats, had a mean prostate weight of 124 mg +/- 8.8 (S.E.M.) compared to the 24.5 mg +/- 1.9 (S.E.M.) of the castrated rat followed under the same regimen (p < 0.01). When castrated rats were given testosterone, the mass increased significantly to 250.0 mg +/- 31.7 (S.E.M.) (p < 0.01). In the five remaining groups, castrated rats receiving testosterone were given finasteride, an extract of Saw Palmetto, crushed whole berry derived from Saw Palmetto fruit, a water soluble and fat soluble extract of Cernitin or a combination of the Saw Palmetto extract and Cernitin. All treatments decreased the size of the prostate to roughly the same size as in the non-castrated rats, a size that was significantly smaller than castrated rats treated with testosterone in the same manner (p < 0.01). A second study examining non-castrated rats treated with very high doses of testosterone showed similar results. In both studies, the nutraceuticals generally decreased body weight. In conclusion, these studies show the ability of Saw Palmetto (whole berry and extract) and Cernitin to influence prostatic hyperplasia via effects on androgen metabolism.

Antihypertensive and metabolic effects of whole Maitake mushroom powder and its fractions in two rat strains.

Maitake mushroom has been reported to favorably influence hypertension and diabetes mellitus. The purpose of this study was to compare the effects of whole Maitake mushroom powder and two extracts designated as ether soluble (ES) and water soluble (WS) on Zucker fatty rats (ZFR), a model of insulin resistance, and on spontaneously hypertensive rats (SHR), a model of genetic hypertension. In the initial study, we followed four groups of eight ZFR and SHR receiving special diets: a baseline diet (BD), BD + whole Maitake mushroom powder (20% w/w), BD + fraction ES (0.10% w/w), and BD + WS (0.22% w/w). Different effects of these dietary regimens on the 2 rat strains were found. At 35 days, only consumption of the ES diet significantly decreased systolic BP (SBP) in SHR (average 197 vs. 176 mm Hg, p < 0.001), while in ZFR only the groups consuming the whole Maitake and WS diets showed significantly decreased SBP (138 vs. 120-125 mm Hg, p < 0.001). A challenge test with losartan (an angiotensin II receptor blocker) indicates that angiotensin II does not play a major role in SBP regulation of ZFR, but does in SHR where consumption of ES relative to other groups significantly lowered activity of this system. In SHR, glucose, cholesterol, circulating insulin and HbA1C were virtually similar among all dietary groups; but whole Maitake (-22%), ES (-120%) and WS (-80%) diets were associated with decreased triglycerides, and the ES diet with lowered serum creatinine (-29%). In ZFR, circulating insulin and HbA1C were significantly decreased in the whole Maitake powder and ES groups, and tended to be lower in the WS group compared to control. In the ensuing studies, we gavaged ZFR once daily with water (control), 44 mg fraction WS, or 44 mg fraction WS plus 100 microg niacin-bound chromium (NBC). Oral gavage of WS clearly lowered SBP and circulating glucose concentrations, more so with the addition of chromium. We conclude that the examined forms of Maitake mushroom have antihypertensive and antidiabetic potential which differ among rat strains. The ES fraction may decrease SBP in SHR via alteration in the renin-angiotensin system.

Effects of Maitake mushroom fractions on blood pressure of Zucker fatty rats.

A link exists between insulin resistance and many chronic disorders of aging including advancing-age. A safer means to prevent or, at least, slow the erosion of insulin sensitivity would provide a novel approach to better health. We compared the ability of a specific extract labeled fraction SX, as well as whole Maitake powder, fraction ES and fraction D of Maitake to influence SBP and various pertinent biochemical parameters when given orally to Zucker Fatty rats, a model of insulin resistance and type 2 diabetes mellitus. A secondary gain was the ability to ascertain the effects of bitter melon, olive oil, and sesame oil alone and combined with fraction SX to influence SBP. We found that a water-soluble fraction obtained from Maitake mushroom (SX) lowers SBP and fasting blood glucose significantly over the three to six weeks of study. While whole Maitake fraction lowered SBP effectively, the effects on fasting blood sugar were not apparent under the conditions of study. In contrast to fraction SX and fraction D, developed primarily to enhance immunity and suppress tumor development and growth, has essentially no effect on SBP under the conditions examined. An ether soluble fraction designated ES lowers SBP significantly. Interestingly, olive oil, unlike sesame oil, also lowers SBP. Finally, bitter melon and a combination of SX plus bitter melon also lower SBP. We conclude that fraction SX of Maitake mushroom may be useful to treat insulin resistance alone or combined with other natural products such as bitter melon and niacin-bound chromium.