Effect of hesperidin on blood pressure and lipid profile: A systematic review and meta‐analysis of randomized controlled trials

The cardioprotective activity of hesperidin has been well demonstrated in several clinical studies. Also, there is a meta‐analysis published on this topic in 2019. However, considering the recently published clinical studies, there is a scope for performing a systematic review and meta‐analysis of hesperidin to determine its beneficial effect in alleviating alterations in cardiovascular parameters. In this study, the literature search was performed using online databases such as PubMed and Google Scholar till April 2023 involving randomized controlled studies conducted on hesperidin against various cardiovascular disorders including metabolic disorders in healthy/diseased individuals compared to the placebo/control. Based on the inclusion and exclusion criteria, nine clinical studies involving 2414 subjects were included. The meta‐analysis revealed that hesperidin has significantly reduced the low‐density lipoprotein (LDL) (IV: −0.55 (−0.94 to −0.16) at 95% CI, p = 0.005, I2 = 70%), total cholesterol (TC) (IV: −61 (−0.82 to −0.41) at 95% CI, p < 0.00001, I2 = 69%), and triglycerides (TG) (IV: −0.21 (−0.40 to −0.02) at 95% CI, p = 0.03, I2 = 12%). However, there were no statistically significant changes in the systolic blood pressure (IV: −0.29 (−2.21 to 1.63) at 95% CI, p = 0.77, I2 = 60%), diastolic blood pressure (IV: 0.79 (−0.74 to 2.31) at 95% CI, p = 0.31, I2 = 49%), and high‐density lipoprotein (IV: 0.04 (−0.25 to 0.34) at 95% CI, p = 0.78, I2 = 56%) in the hesperidin treatment compared to the placebo/control. In conclusion, the outcomes of this meta‐analysis suggest that hesperidin administration could benefit patients with CVD by reducing LDL, TC, and TG. Further high‐quality studies are needed to firmly establish the clinical efficacy of hesperidin for its benefits in treating cardiovascular conditions.


| INTRODUCTION
As per the World Health Organization (WHO) fact sheet, cardiovascular diseases (CVDs) are the major cause of death globally (WHO, 2021).WHO estimated that 17.9 million people died from CVDs in the year 2019, which was 32% of all-cause deaths globally (WHO, 2021).Cardiovascular disorder is a broad term that covers coronary heart disease, rheumatic heart disease, cerebrovascular disease, deep vein thrombosis/pulmonary embolism, congenital heart disease, and peripheral arterial disease.Coronary heart disease is the most common among these CVDs (Prabhakaran et al., 2016).Most CVDs are easily preventable regardless of being a foremost cause of mortality globally (Kinoshita et al., 2018) with dietary control (Clar et al., 2017), high-intensity workouts, active lifestyle (Lavie et al., 2015), and stress management.CVDs are often due to metabolic imbalance (Zhang et al., 2008).Under such conditions, there is a nutritive disparity between supply and demand, which leads to heartrelated disorders such as obesity, atherosclerosis, hypertension, ischemic heart disease, and occasionally, heart failure (Brandhorst & Longo, 2019).These disorders are associated with oxidative stress at the cellular level due to mitochondrial dysfunction (Ferrari, 1996).Further, elevated blood pressure (particularly systolic blood pressure [SBP]) is known to cause damage to the inner walls of the aorta (endothelium) and thereby leads to coronary artery diseases (CAD), stroke, and renal diseases (Antikainen et al., 1998;Balahura et al., 2022).The previously published randomized controlled trials (RCTs) suggest that an average reduction of 12-13 mm Hg in SBP over 4 years of followup resulted in a 21% reduction in coronary heart disease, 25% reduction in total cardiovascular mortality, and 13% reduction in all-cause mortality rates (He & Whelton, 1999).Moreover, the available clinical study data infer that altered lipid profile, namely elevated triglycerides, total cholesterol (TC), low-density lipoprotein (LDL), and very low-density lipoprotein, with a decrease in high-density lipoprotein (HDL), is the major risk factor in the pathogenesis of CAD and cerebrovascular disease (Dong et al., 2021).
Hesperidin is a polyphenolic compound found most abundantly in citrus fruits that has many medicinal uses.Hesperidin has been found to induce many pharmacological activities like hypolipidemic, antidiabetic, anti-inflammatory, and antihypertensive effects.Relevant to this study, to date, there are 13 clinical studies related to the cardioprotective activity of hesperidin in humans.Also, one meta-analysis study has been published so far (Mohammadi et al., 2019).However, the metaanalysis performed by Mohammadi et al. considered the studies on orange juice and hesperidin, the comparisons were not solely between hesperidin versus placebo/control.Further, two additional randomized controlled trials, Yari et al., 2020 andYari et al., 2021 have been published on hesperidin related to its cardiovascular benefits after the publication of the above-cited meta-analysis papers.Therefore, there is a scope for performing a systematic review and meta-analysis on hesperidin related to its cardiovascular benefits compared to placebo/control.With this background, the present study was undertaken to carry out a systematic review and meta-analysis to determine the beneficial role of hesperidin in treating cardiovascular diseases.

| Literature search
The literature search was performed in detail using the search term "Hesperidin" in combination with cardiovascular disease, heart, and clinical trials in online databases such as PubMed and Google Scholar for studies published up to April 2023.Initially, all the articles obtained from the above databases were screened with the "abstract" or "full-length copy," and irrespective of the type of experimental model, the articles fitting into the inclusion criteria were considered for the study.Further, cross-references in the articles and reviews were searched wherever additional data were required.
The literature search was entirely performed by H Shylaja, GL Viswanatha, and Sunil V; however, after considering all the co-authors, the final selection of articles for systematic review and meta-analysis was performed with inclusion and exclusion articles.

| Inclusion criteria
The original research articles published until April 2023 involved randomized controlled studies conducted on hesperidin against various cardiovascular disorders including metabolic disorders in healthy/ diseased individuals compared to placebo/control.
2. Studies performed without control.
3. Studies involving combination formula or other ingredients with hesperidin.

| Parameters
The meta-analysis was performed for cardiovascular parameters such as blood pressure (both diastolic blood pressure [SBP] and diastolic blood pressure [DBP]) and lipid profile (LDL, HDL, TC, and triglycerides [TG]).The above-listed parameters were compared between the control and hesperidin-treated groups.

| Risk of bias (RoB) assessment for the included studies
Cochrane Collaboration's risk assessment tool (version 5.4.1) for RCTs was used to evaluate the methodological quality of the included studies.The tool evaluated six potential risks of bias: random sequence generation, allocation concealment, blinding of participants, blinding of outcome assessment, incomplete outcome data, and selective reporting.Each item was judged by the following criteria: low risk of bias, uncertain risk of bias, and high risk of bias.Whenever studies included three or more high risks of bias, they were considered as having poor methodological quality.Three reviewers (SH, GLV, and SV) checked the profile of each included study independently.Any discrepancies in the risk of bias scores were resolved by consultation with a fourth reviewer.

| Quality of evidence assessment (GRADE analysis)
The outcomes of all the parameters were subjected to quality of evidence assessment GRADE profiler version 3.6 along with the consensus of two authors (SH and GLV) according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system (Guyatt et al., 2008).In this system, the quality of the RCTs is initially graded as high and later can be downgraded considering the attributes such as (1) risk of bias, (2) inconsistency, (3) indirectness, (4) imprecision, and (5) publication bias.This system divides the quality of evidence into four categories: high, moderate, low, and very low (Balshem et al., 2011;Guyatt et al., 2008;Schünemann et al., 2011Schünemann et al., , 2023)).

| Data collection and analysis
All the studies were critically scrutinized distinctly as per the inclusion and exclusion criteria by the reviewers.The analysis was done initially at the title and abstract level, and later at the full-text level.
Data to be pulled out from the studies included, such as details of experimental conditions, methods used, interventions, and outcome measurements.Wherever necessary, the numerical data from the graphs were extracted using Adobe Acrobat's XI in-built measuring tool (Adobe Systems Incorporated, San Jose, CA, USA).Further, in the absence of a standard error of the mean (SEM) or standard deviation (SD), a default value of 10% of the mean was considered as SD for both hesperidin and control groups, instead of assigning zero.

| Statistical analysis
The meta-analysis was performed using Review Manager (RevMan, version 5.4; Nordic Cochrane Centre [Cochrane Collaboration], Copenhagen, Denmark; 2014).For continuous variables, inverse variance (IV) was estimated using the random-effects model with a standardized mean difference (SMD) as the effect measure.A random-effects model was used to calculate the pooled prevalence with a 95% confidence interval (CI).
Heterogeneity was calculated with the I 2 statistic.This test evaluated the percentage of the difference between the results of the study that is due to heterogeneity rather than sampling error.An I 2 of less than 40% was considered as not significant.On the other hand, an I 2 value of more than 40% was regarded as moderate to high heterogeneity.

| Selection of articles
During the electronic search, a total of 2905 records were identified across various databases, namely, PubMed/Medline (n = 84) and Google Scholar (n = 2820) based on the pre-defined search criteria.Upon applying the inclusion and exclusion criteria a total of nine research articles were selected for systematic review meta-analysis out of 2905 records identified during the preliminary search (Annexure 1 and 2).
The duration of the included studies varied from a single day to multiple days.In all the included studies the pure form of hesperidin was used at different dose levels.The search strategy and descriptions of the studies included in this systematic review and meta-analysis have been summarized in Figure 1 and Table 1, respectively.

| Risk of bias in the included studies
The included studies were evaluated for risk of bias against seven standard parameters, and each parameter was rated as either high risk or low risk; where the risk was not clear, it was rated as unclear risk.
Among the nine included studies, three studies (Morand et al., 2011;Salden et al., 2016;Yari et al., 2021) have been considered to have a combination of two high risks along with one unclear risk.One study (Haidari et al., 2015) was considered to have one high risk along with one unclear risk.The remaining five studies (Demonty et al., 2010;Homayouni et al., 2018;Ohara et al., 2016;Rizza et al., 2011 andYari et al., 2020) were considered to have 1-2 unclear risks along with low risks for the rest of the parameters.Overall, the quality of the included studies was low to high.The risk of bias assessment for included studies is included in Figure .2.

| Quality of evidence for outcomes (GRADE analysis)
The quality of evidence for outcome measures according to the GRADE system is presented in Table 2.The quality of evidence was rated from low to high for the evaluated outcomes.In the outcomes where hesperidin has shown significant effect, the weight of evidence was low for SBP, DBP, HDL; moderate for TG, and high for LDL and TC.

| Effect of hesperidin on blood pressure
The effect of hesperidin on blood pressure has been evaluated across various studies.However, this meta-analysis revealed no statistically significant difference in SBP (IV: À0.29 (À2.21 to 1.63) at 95% CI, p = 0.77, I 2 = 60%) and DBP (IV: 0.79 (À0.74 to 2.31) at 95% CI, p = 0.31, I 2 = 49%) in the hesperidin treated groups compared with control.There was a significant heterogenicity among the included studies for SBP and DBP.Based on the available evidence, hesperidin administration has not shown potential benefit in reducing SBP and DBP, though there was a trend in some of the included studies.The heterogenicity among the included studies may be one of the potential reasons for the lack of statistical significance in the hesperidin group compared to the placebo.The results are depicted as forest plots in Fig-

| Effect of hesperidin on lipid profile
The lipid profile such as TC, TG, LDL, and HDL has a great correlation with cardiovascular health.Particularly, elevated serum levels of LDL, TC, TG, and decreased HDL levels have a negative impact on cardiovascular health and are hence considered potential risk factor/s in the The results are illustrated as forest plots in Figures 5-8.

| DISCUSSION
The systematic review and meta-analysis are considered at the top of the hierarchy of the clinical evidence.In this approach, the data Notably, this meta-analysis revealed that hesperidin administration has not shown statistically significant differences in SBP and DBP compared to the placebo/control.Further, the significant heterogenicity among the included studies may be one of the potential reasons for the lack of statistical significance in blood pressure parameters among the hesperidin-treated group compared to placebo/control.
F I G U R E 7 Effect of hesperidin on triglycerides.
F I G U R E 8 Effect of hesperidin on total cholesterol.
Numerous studies show that the increase in the levels of TG and TC might affect the contraction of blood vessels in the heart, which is significantly associated with the risk of cardiovascular disease.Furthermore, increases in the level of LDL could induce arteriosclerosis due to the buildup of LDL in the intima-media of the arteries, which in turn leads to thrombosis (Esmaeili & Ahmadi, 2004;Gąsecka et al., 2021).As per available scientific data, HDL is inversely proportional to cardiovascular disease.Higher the HDL level, the lesser the risk of emerging cardiovascular disease.It is also believed that HDL acts by reverse cholesterol transport where HDL interacts with cells in systemic vasculature by a series of reactions and disposes of excess cholesterol as bile salts by transferring it to the liver (Filippatos & Elisaf, 2013).Medicines that are used to lower the lipid profile are of two types, namely, statins (e.g., lovastatin, simvastatin, fluvastatin, atorvastatin, rosuvastatin, etc.) and fibrates (e.g., ciprofibrate, clofibrate, fenofibrate, etc.) (Pahan, 2006).Based on the available literature, some of the herbs and herbal supplements can also be used for lowering lipid profile.Some of the herbs containing hypolipidemic agents are basil, ginger, dill oil, tea, grapes, and so on (Rouhi-Boroujeni et al., 2015).
This systematic review and meta-analysis revealed that the administration of hesperidin has alleviated the LDL, TC, and triglycerides levels compared to placebo/control in the subjects with cardiovascular diseases.However, hesperidin administration has not elicited a beneficial effect on HDL compared to the placebo/control.
In summary, this systematic review and meta-analysis revealed that the administration of hesperidin has alleviated LDL, TC, and triglycerides in subjects with cardiovascular diseases.However, there is no beneficial effect of the administration of hesperidin on SBP, DBP, and HDL compared with the placebo/control.However, the heterogenicity between the studies is considered as one of the concerns for all the parameters evaluated except triglycerides.The outcome of this meta-analysis is slightly in contrast to the findings of

| LIMITATIONS
Though there are several clinical studies published on hesperidin related to its cardiovascular benefits, in this meta-analysis, we found hesperidin is beneficial in alleviating only elevated serum levels of LDL, TC, and TG.However, the trend shows that hesperidin has also got the potential to alleviate SBP, DBP, and other lipid parameters, despite these changes not reflecting in the summary because of the significant heterogenicity between the included studies.The possible reasons may be differences in the population included (both diseased and healthy individuals), and the fact that available studies were conducted at different locations by different study groups with different study characteristics.There is further scope for conducting multicentric, double-blind placebo-controlled trials involving patients with underlying cardiovascular conditions.

| CONCLUSION
Based on the available evidence, the present systematic review and meta-analysis suggest that hesperidin supplementation could be an adjuvant in alleviating the elevated levels of serum LDL, TC, and triglycerides in patients suffering from cardiovascular diseases.

F
I G U R E 2 Risk of bias (RoB) of included studies.T A B L E 2 GRADE evidence profile: hesperidin compared to placebo/control.pressure (SBP) (follow-up mean 3-12 weeks; range of scores: À2.21 to 1.63; better indicated by lower values) pressure (DBP) (follow-up mean 3-12 weeks; range of scores: À0.74 to 2.31; Better indicated by higher values) lipoprotein (LDL) (follow-up mean 3-12 weeks; range of scores: À0.94 to 0.16; better indicated by lower values) lipoprotien (HDL) (follow-up mean 3-12 weeks; range of scores: À0.25 to 0.34; better indicated by lower values) TC) (follow-up mean 3-12 weeks; range of scores: À0.82 to 0.41; Better indicated by lower values) CI: Confidence interval; GRADE Working Group grades of evidence.High quality: Further research is very unlikely to change our confidence in the estimate of effect.Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.Very low quality: We are very uncertain about the estimate.a One of the study was open-label, there is a risk of bias.b There was inconsistency among the studies in reporting the effect on SBP, I 2 = 60%.c There was inconsistency among the studies in reporting the effect on DBP, I 2 = 49%.d There was inconsistency among the studies in reporting the effect on HDL, I 2 = 56%.available across different clinical/pre-clinical studies will be evaluated comprehensively from various perspectives to conclude the quality and reliability of the outcomes, and finally help in deriving a meaningful and conclusive statement about the outcomes of the research.In short, if there are several clinical studies available on a drug/herb/phytochemical, all the available data will be considered, F I G U R E 3 Effect of hesperidin on systolic blood pressure.F I G U R E 4 Effect of hesperidin on diastolic blood pressure.F I G U R E 5 Effect of hesperidin on low-density lipoprotein.F I G U R E 6 Effect of hesperidin on high-density lipoprotein.and subjected to detailed statistical analysis; the recommendations will be made based on the outcomes of the statistical analysis.In this regard, there are several clinical studies published on the cardiovascular benefits of hesperidin.In addition, a meta-analysis published by Mohammadi et al. (2019) reported that hesperidin supplementation does not affect blood pressure and lipid profile.However, Mohammadi et al. have considered the studies published on both orange juice and hesperidin, and secondly, the comparisons were not solely between hesperidin versus placebo/control.Furthermore, there are two additional randomized control trials published on hesperidin related to its cardiovascular effects after the publication of the abovecited meta-analysis.The present systematic review and meta-analysis was performed to determine the beneficial effect of hesperidin in alleviating the altered blood pressure and lipid profile among patients with cardiovascular diseases.The clinical studies published up to 2021, showing a comparison between hesperidin versus placebo/control, were considered.Worldwide, there are about 1.28 billion people aged 30-79 years with hypertension.Hypertension is one of the major causes of premature death and cardiovascular disease globally.It can cause damage to the arteries and cells of the inner lining of blood vessels.When fat enters the bloodstream through diet, it can accumulate in these damaged arteries.Eventually, the walls of the arteries become less elastic and limit the flow of blood throughout the body, which leads to cerebrovascular diseases like CAD (angina, arrhythmia, and heart attack), heart failure, transient ischemic attack, stroke, dementia, and mild cognitive impairment.As per the available literature, treatment for lowering blood pressure significantly reduces the risk of cardiovascular disease and death (WHO; 2023).Reduction of SBP by 10 mm Hg reduces the risk of heart failure by 28%, cardiovascular disease by 20%, stroke by 27%, coronary heart disease by 17%, and allcause mortality by 13% (Ettehad et al., 2016).Lifestyle modifications like quitting smoking and tobacco, being more active, and having a healthier diet may reduce the risk of hypertension.Some patients still need medicines to lower their blood pressure.Medicines that are commonly used to treat hypertension are ACE inhibitors (e.g., enalapril and lisinopril), calcium channel blockers (e.g., amlodipine and felodipine), angiotensin-2 receptor blockers (e.g., losartan and telmisartan), and diuretics (e.g., hydrochlorothiazide and chlorthalidone) (WHO 2023).Apart from these allopathic medicines, some herbs and their supplements are also used to treat hypertension.The most commonly used herbs for the treatment of hypertension are garlic (Allium sativum), custard apple (Annona muricate), tea (Camellia sinensis), ajwain (Carum copticum), carrot (Daucus carota), flaxseed (Linum usitatissimum), tomato (Lycopersicon esculentum), basil (Ocimum basilicum), pomegranate (Punica granatum), radish (Raphanus sativus), flavonoids, polyphenols, and so on (Tabassum & Ahmad, 2011).Hesperidin reduces blood pressure by decreasing oxidative stress through the renin-angiotensin system cascade suppression (Mas-Capdevila et al., 2020).
Mohammadi et.al, related to LDL, TC, and triglycerides.The possible reasons may be firstly, Mohammadi et al. have considered the studies published on both orange juice and hesperidin, secondly, in Mohammadi et al., the comparisons were not solely between hesperidin versus placebo/control, and lastly, in this meta-analysis, two additional randomized controlled trials published on hesperidin have been included.