Yin Shao, Zhu Fengya, Zhou Qian, Chen Miao, Wang Xia, Chen Qiu
Hospital of Chengdu, University of Traditional Chinese Medicine, Chengdu, China.
Traditional Chinese Medicine Department, Zigong First People's Hospital, Zigong, China.
Phytother Res. 2025 Jan;39(1):77-89. doi: 10.1002/ptr.8362. Epub 2024 Nov 5.
The objective of this study is to assess the impact of pomegranate supplements on insulin resistance (IR) and insulin sensitivity through a systematic review and meta-analysis of randomized controlled trials (RCTs). Additionally, we aim to analyze the differences in efficacy among various pomegranate extracts and the sensitivity of different diseases to pomegranate supplementation. We conducted searches in PubMed, Embase, Web of Science, and Cochrane Library up to October 30, 2023, for relevant studies published in English. The treatment group required the intake of pomegranate extract for a minimum of 4 weeks, with no restrictions on the extract type. The control group received a placebo or a treatment excluding pomegranate extract. The primary outcome was homeostatic model assessment for insulin resistance (HOMA-IR) and fasting insulin (FI), and the secondary outcome was quantitative insulin sensitivity check index (QUICKI). RoB 2 was used to assess the risk of bias in the original studies. We pre-specified subgroup analyses based on types of intervention, intervention duration, health condition, and intervention dose. Sensitivity analysis was conducted to validate result stability, utilizing Begg's test and Egger's test for publication bias. Data synthesis and analysis were performed using Stata 15.1 software. This study included a total of 15 RCTs with 673 participants conducted in 7 countries. Risk of bias results indicated an overall low risk of bias of the articles. Participants included healthy individuals, overweight and obese individuals, non-alcoholic fatty liver disease (NAFLD) patients, type 2 diabetes (T2DM) patients, polycystic ovary syndrome (PCOS) patients, metabolic syndrome (MS) patients, and individuals with hyperlipidemia. Pomegranate extract variations included pomegranate juice (PJ), pomegranate seed oil (PSO) capsule, pomegranate/pomegranate peel (PP) extract capsule, and pomegranate peel-added bread. The control groups primarily received placebo treatments with varying dosage and frequency. No adverse reactions were reported in any of the studies. The summary results showed that compared to the control groups, pomegranate extract had no significant impact on improving HOMA-IR levels in participants (WMD = -0.03, 95%CI: -0.37 to 0.31, and p = 0.851) and FI (WMD = -0.03, 95%CI: -0.42 to 0.36, and p = 0.862). Additionally, there was no significant advantage of pomegranate extract on QUICKI changes in T2DM and PCOS patients (WMD = 0.00, 95%CI: 0.00 to 0.01, and p = 0.002). Subgroup analysis results indicated that pomegranate extract could improve HOMA-IR levels in PCOS patients (WMD = -0.42, 95%CI: -0.54 to -0.29, and p < 0.001) and FI levels in T2DM, PCOS, and NAFLD patients. Our results indicate that pomegranate extract only improves HOMA-IR and FI levels in PCOS patients and FI levels in T2DM and NAFLD patients. No significant difference has been found for HOMA-IR, FI, or QUICKI in other metabolic diseases. The current evidence suggests that we should interpret the value of pomegranate extract in regulating IR and sensitivity cautiously. In the future, there is a need for more rigorously designed RCTs to specifically evaluate the impact of pomegranate supplementation on insulin sensitivity in patients with NAFLD, PCOS, and T2DM.
本研究的目的是通过对随机对照试验(RCT)进行系统评价和荟萃分析,评估石榴补充剂对胰岛素抵抗(IR)和胰岛素敏感性的影响。此外,我们旨在分析各种石榴提取物之间的疗效差异以及不同疾病对石榴补充剂的敏感性。我们在截至2023年10月30日的PubMed、Embase、Web of Science和Cochrane图书馆中检索了以英文发表的相关研究。治疗组需要摄入石榴提取物至少4周,对提取物类型没有限制。对照组接受安慰剂或不含石榴提取物的治疗。主要结局是胰岛素抵抗的稳态模型评估(HOMA-IR)和空腹胰岛素(FI),次要结局是定量胰岛素敏感性检查指数(QUICKI)。采用RoB 2评估原始研究中的偏倚风险。我们预先指定了基于干预类型、干预持续时间、健康状况和干预剂量的亚组分析。进行敏感性分析以验证结果的稳定性,利用Begg检验和Egger检验评估发表偏倚。使用Stata 15.1软件进行数据合成和分析。本研究共纳入了7个国家进行的15项RCT,涉及673名参与者。偏倚风险结果表明文章总体偏倚风险较低。参与者包括健康个体、超重和肥胖个体、非酒精性脂肪性肝病(NAFLD)患者、2型糖尿病(T2DM)患者、多囊卵巢综合征(PCOS)患者、代谢综合征(MS)患者和高脂血症患者。石榴提取物的种类包括石榴汁(PJ)、石榴籽油(PSO)胶囊、石榴/石榴皮(PP)提取物胶囊和添加石榴皮的面包。对照组主要接受不同剂量和频率的安慰剂治疗。所有研究均未报告不良反应。汇总结果显示,与对照组相比,石榴提取物对改善参与者的HOMA-IR水平(加权均数差[WMD]=-0.03,95%置信区间[CI]:-0.37至0.31,p=0.851)和FI水平(WMD=-0.03,95%CI:-0.42至0.36,p=0.862)没有显著影响。此外,石榴提取物对T2DM和PCOS患者的QUICKI变化也没有显著优势(WMD=0.00,95%CI:0.00至0.01,p=0.002)。亚组分析结果表明,石榴提取物可以改善PCOS患者的HOMA-IR水平(WMD=-0.42,95%CI:-0.54至-0.29,p<0.001)以及T2DM、PCOS和NAFLD患者的FI水平。我们的结果表明石榴提取物仅能改善PCOS患者的HOMA-IR和FI水平以及T2DM和NAFLD患者的FI水平。在其他代谢性疾病中,未发现HOMA-IR、FI或QUICKI有显著差异。目前的证据表明,我们应谨慎解读石榴提取物在调节IR和敏感性方面的价值。未来,需要更严格设计的RCT来具体评估石榴补充剂对NAFLD、PCOS和T2DM患者胰岛素敏感性的影响。