Спирулина Spirulina Научные исследования Спирулина в клинической практике: доказательства, основанные на человеческих приложений



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Discussion


To our knowledge, this pilot study is the first human trial to address the effects of Spirulina supplementation on liver function and health-related quality of life in patients with NAFLD. Our study yielded outcomes that showed beneficial effects of Spirulina supplementation within observed parameters on 15 NAFLD Cretan outpatients, including a significant reduction in serum liver enzymes and lipids, and additionally an improvement in scores on health-related quality of life.

In our study, Spirulina supplementation (6 g/day for 6 months) decreased AST and ALT levels by 38.5% and 37.5%, respectively. This indicates a hepatoprotective effect of Spirulina (aminotransferases reduction) on NAFLD patients, previously also recorded in three Mexican patients (one 43-year-old male with BMI 26 kg/m2; one 77-year-old male with BMI 29.9 kg/m2; and one 44-year-old female with BMI 30 kg/m2) with NAFLD (as evidenced by US and serum ALT data) and dyslipidemia [26]. The consumption of 4.5 g/day of A. maxima in tablet form for three months by these patients decreased the pathological levels of serum ALT (an average decrease of 41%), T-C, triacylglycerols (TAG), LDL-C and AI [26]. Several previous animal studies, but a limited number of clinical trials on humans with IR and NAFLD, have suggested that hepatoprotective properties of Spirulina are related with its antioxidant and anti-inflammatory properties (mainly due to C-phycocyanin, β-carotene, and vitamin E) and the reduction in liver lipid profile [26-38]. Using a single intra-peritoneal dose of 1 mL/kg carbon tetrachloride (CCl4) as a hepatotoxic in order to induce NASH, it was demonstrated that 5% A. maxima in the diet of rats decreases serum AST, liver TAG and T-C [31]. An identical pattern was discerned in the liver free fatty acids (with a significant decrease in unsaturated fatty acids) and the thiobarbituric acid reactive substances, indicators for lipoperoxidation [33]. Furthermore, it has been shown that A. maxima inhibits the development of fatty liver induced by simvastatin, ethanol and hypercholesterolemic in mice [34], and A. fusiformis is protective against chemical-mediated genotoxicity in mice by intensifying the activity of cellular antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase [38]. Spirulina has revealed its antioxidant and/or anti-inflammatory activity in humans by reducing inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α and increasing anti-inflammatory protein adiponectin indicating a reduction of oxidative stress [28-30]. It is known that in NAFLD, inflammatory cytokines IL-6 and TNF-α are elevated, while adiponectin is lowered [39]. In addition, Spirulina supplementation, as a low-calorie, low-fat, and cholesterol-free source of protein, could contribute to the reduction in intrahepatic triglyceride content [40,41].

Dyslipidemia is often associated with NAFLD and regarded as a risk factor for fatty infiltration of the liver [42-44]. Our study revealed that all the undesirable lipid fractions (T-C, TG, LDL-C) were substantially reduced at the end of the 6-month period of Spirulina supplementation, with the major reduction being observed in TG levels (-24.8%). These findings are expected, considering the results of our previous study conducted in a Cretan population with the same product but at a lower dosage (1 g/day) [1]. However, the increase of HDL-C levels (4.2%) among the 15 NAFLD patients was statistically significant (P=0.0002). The active ingredients in Spirulina that produce its hypolipidemic activity still remain unidentified. Nonetheless, it was discovered in studies on rats that an element contained in Spirulina (A. platensis) inhibited jejunal cholesterol absorption and ileal bile acid reabsorption, and it was suggested C-phycocyanin produced these effects [45]. Another study using rats reported findings that a glycolipid, determined to be glycolipid H-b2 isolated from Spirulina, inhibited pancreatic lipase activity in a dose-dependent manner and also lowered postprandial TG levels [46]. The same study revealed that phycocyanin also inhibits pancreatic lipase [46]. An alternative suggestion is that the hypolipidemic effect of Spirulina in our study could be attributed to its essential polyunsaturated (omega-6 and omega-3) fatty acids [mainly γ-linolenic acid (1960 mg/100 g), linolenic acid (139 mg/100 g) and α-linolenic acid (311 mg/100 g)] and niacin (vitamin B3, 10.8 mg/100 g)[1]. Moreover, the significant improvement of HOMA-IR index (-19.6%) in our study patients might contribute to the reduction of LDL-C levels, considering that the expression of hepatic LDL receptors is inversely related to IR and the availability of cholesterol [44,47]. Also, it is known that BW loss alters the metabolic fate of HDL particles by decreasing plasma TG levels and delays the catabolism of HDL apoA-I with a concomitant reduction in the secretion of HDL apoA-I [44,47].

Even though current scientific evidence regarding Spirulina supplementation for BW is unsatisfactory [1], our findings revealed substantial BW loss (-8.1%) accompanied by a significant reduction of HOMA-IR index (-19.6%) following Spirulina supplementation among the 15 participants. The discrepancy between our BW findings and previous studies [1] might be due to the higher dose and longer period of administration (6 g/day for six months instead of 1g/day for 3 months). However, this BW loss is remarkable considering that a moderate BW loss (5-10% of baseline BW) has a beneficial effect on cardiovascular risk factors, such as diabetes mellitus type 2, hypertension and hyperlipidemia [48,49]. Moreover, a gradual BW loss through improved diet and increased physical activity is the main guideline for the management of NAFLD [50], the cornerstone therapy of NAFLD, improving liver enzymes, insulin sensitivity, reducing inflammation and liver histology [6,51-56]. The BW loss could be explained mainly by the low fat and low carbohydrates content of Spirulina supplementation which is far lower than almost all other protein sources [1]. Research has demonstrated that BW loss with a low-fat diet reduces IR and cholesterol synthesis, and modifies fat liver in overweight non-diabetic subjects [40,57]. Spirulina supplementation also contains phenylalanine, a potent releaser of cholecystokinin that acts on the brain’s appetite center, which in turn acts as a BW suppressant [58-60]. Although the patients were encouraged for changes in their lifestyle habits (dietary or physical activity habits) before their enrolment in our study, assessment of these habits throughout the study was not performed. So, potential changes in participants’ lifestyle habits – that may have contributed to the observed weight loss – cannot be excluded. The beneficial effect of Spirulina supplementation on the haemoglobin levels in our study is due to its hematopoietic nutrients (such as protein, iron, folic acid, vitamin B12) and is known from previous studies [61-64]. The beneficial role of Spirulina and a confirmation of its safety profile were revealed with the improvement to health-related quality of life scale, the lack of adverse reactions and discomfort, and absence of complaints throughout the study.

It is known that diet is a major contributor to NAFLD. Not only the amount of energy but also the quality of the diet plays an important role in the development and progression of NAFLD [6]. Diets rich in saturated fat, cholesterol, and low in saturated fat, fiber and antioxidant vitamins C and E have been associated with NAFLD, IR and hepatic inflammation [6]. So, the composition of Spirulina (low in saturate fat and carbohydrates, rich in polyunsaturated fatty acids, vitamins and dietary fiber) makes it attractive for the management of NAFLD.

Despite the hepatoprotective effects of Spirulina supplementation on our study population, a US change of steatosis among NAFLD patients was not revealed. This finding was not surprising considering that although a US is a widely available and low-cost technique, it is not quantitative or strongly correlated with histopathologic steatosis assessment; nor is it able to display variations across steatosis grades [65,66]. Only a liver biopsy before and after Spirulina supplementation could demonstrate a change on the histopathologic grading of hepatic steatosis. Among imaging techniques, T1-weighted dual-echo MR imaging and 1H MR spectroscopy appear to have the best diagnostic accuracy in depicting hepatic steatosis, in contrast to US and CT [65]. Unfortunately, they were not available in our hospital.

Despite the limitations of the present study, i.e. pilot study, small sample size, lack of control group and assessment of dietary or physical activity habits throughout the study, no blind protocol, no histological evidence, it uncovered remarkable multiple metabolic effects which are beneficial to preventing cardiovascular disease (the most common cause of death) in outpatients with MetS and NAFLD. Thus, the role of Spirulina supplementation as a natural food supplement in NAFLD patients should not be overlooked.

In conclusion, the results of this study demonstrate that Spirulina (A. platensis) supplementation at a high dose of 6 g daily exhibits marked and multiple beneficial metabolic effects and boosts health-related quality of life. We suggest that Spirulina supplementation could be used as a dietary supplement on NAFLD patients. Further studies will be necessary to determine the mechanism(s) of Spirulina’s action on metabolic parameters.



Что уже известно:

  • Спирулина является микроскопических и нитчатые цианобактерии с высокой питательной ценности, принятые в качестве безопасной пищевой добавки для людей и животных.

  • Виды Спирулины показали обмена веществ (гиполипидемическое, гипогликемическое), анти-вирусные, печени-защита и кровеносных сосудов, релаксирующим действием, анти-рак, анти-воспалительными и антиоксидантными свойствами

  • Проверенных эффективных терапий по управлению неалкогольная жировая болезнь печени (НАЖБП) не существует. Краеугольный камень терапии НАЖБП направлена на потерю веса, изменения образа жизни, коморбидность и управления

Какие новые выводы:

  • Спирулина (Arthrospira platensis с) добавок при высокой дозировке 6 г в день у пациентов с НАЖБП имеет сильную и несколько благотворные метаболические эффекты и улучшает их связанное со здоровьем качество жизни

  • Спирулина добавок может быть использован в качестве безопасной и эффективной пищевой добавкой на больных НАЖБП

What is already known:

  • Spirulina is a microscopic and filamentous cyanobacterium with high nutritional value taken as a safe dietary supplement for both humans and animals

  • Species of Spirulina have exhibited metabolic (hypolipidemic, hypoglycemic), anti-viral, liver-protecting and blood-vessel relaxing effects, anti-cancer, anti-inflammatory and anti-oxidant properties

  • Proven effective therapies for the management of non-alcoholic fatty liver disease (NAFLD) do not exist. The cornerstone therapy of NAFLD is directed toward weight loss, lifestyle modifications, and comorbidity management

What the new findings are:

  • Spirulina (Arthrospira platensis) supplementation at a high dosage of 6 g daily in NAFLD patients has strong and multiple beneficial metabolic effects and improves their health-related quality of life

  • Spirulina supplementation could be used as a safe and effective dietary supplement on NAFLD patients


Эффект Arthrospira platensis с капсулы на CD4 + Т-клеток и антиоксидантной емкости в рандомизированном экспериментальном исследовании взрослых женщин, инфицированных вирусом иммунодефицита человека не под ВААРТ в Яунде, Камерун.

Биологически активные добавки часто используются для улучшения питания людей, живущих с ВИЧ/СПИДом (ЛЖВ). Arthrospira platensis с (АСП), также известных как Спирулина это цианобактерии, богатые белками и микроэлементами. Сотовый и доклиническим описано иммуномодулирующее, антиоксидантное и антиретровирусных деятельности. Это пилотное исследование описывает влияние добавки 5 г/день Жерех на пре-высоко-активной антиретровирусной терапии (пред-ВААРТ), ВИЧ-инфицированных, взрослого женского населения. Он проводился в качестве трехмесячного рандомизированного контролируемого исследования (РКИ), что по сравнению чашка добавлением пяти граммов/сутки АСП с плацебо равных содержанием белка и энергии. В исследование были включены 73 ВИЧ-инфицированных женщин. Непосредственный результат переменные были CD4 Т-клеток, вирусной нагрузки и активации иммунной системы по СД8 Т-клеток, экспрессирующих cd38 более всего. Антиоксидантный статус оценивали по общей антиоксидантной емкости сыворотки крови (ТАОС). Функция почек была задокументирована путем креатинина, мочевины и рассчитанная скорость клубочковой фильтрации. Статистические анализы проводились с помощью непараметрических тестов, и размер влияния каждого взаимодействия был вычислен. Никаких различий в иммунологических и вирусологических маркеров между asp и группе плацебо наблюдалось. В группе плацебо, 21 из 30 больных (70%) развились сопутствующие события, в то время как в asp группе, только 12 из 28 пациентов (43%) сделал. Обеих группах зарегистрировано значительное увеличение веса; 0,5 кг (р < 0,05) в asp группе и 0,65 кг (р < 0,05) в группе плацебо. Антиоксидантный потенциал рост 56 (1-98) мкм для asp значительно отличался от снижение наблюдалось в группе плацебо (р < 0,001). Незначительное повышение уровня креатинина в 0,1 г/дл (р < 0,001) наблюдалось в asp группе, и отсутствие эффекта наблюдалось в уровнях мочевины. Улучшение антиоксидантного потенциала в asp, показаны впервые на ЛЖВ, могут стать основой для будущих исследований о питании и здоровье Спирулина. Наблюдаемое незначительное, но достоверное увеличение сывороточного креатинина требует дальнейшей оценки, особенно с разной дозы АСП.



Nutrients. 2014 Jul 23;6(7):2973-86. doi: 10.3390/nu6072973.



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