In vitro impact of the long term medication for blood pressure, diabetes type II and cholesterol medicines on the gut microbiota

1 Introduction

Microorganisms commence colonizing the human body by the first moments of birth (Milani et al., 2017). The community of such collection of microbes is called the microbiome. This term includes these microorganisms and all related genetic materials and the secreted substances of these microbes that occupy the human body (Mousa et al., 2022). The microbiota of humans is a very complex community and dynamic changes are occurring in these microorganisms during the different human age levels, nevertheless, the stage after adulthood and before aging represents the most stable period for gut microbiota which contribute to host growth (Thursby and Juge, 2017; Herzog et al., 2021). Consequently, human health is regulated positively or negatively by the microbiota that is inhabited in or on the body organs (Vos et al., 2022). A direct relationship between gut microbiota and the host health was reported. These microorganisms, particularly probiotics, contribute in metabolizing nutrients, digesting polysaccharides that are complex and indigestible and providing the essential molecules that the host-body lack its pathways to synthesize substances such as certain vitamins as well as protecting against pathogens and evolving the immune system (Lazar et al., 2019). For instance, the short-chain fatty acids (SCFAs) as gut microbiota secondary metabolites (Silva et al., 2020). SCFAs are short-chain organic molecules composed of less than 6 carbon atoms, such compounds are produced as a result of fermentation of complex polysaccharides by obligate anaerobic bacteria in the large intestine (Den Besten et al., 2013). Acetate, butyrate and propionate are the notable SCFAs that demonstrated to play a significant role in human health through protecting from inflammatory response, inducing mucus production, preserving intestinal barrier integrity, enhancing insulin secretion and minimizing the risk of colon cancer as well as inhibiting the activity of histone deacetylase (HDAC) that effect on brain functions (Markowiak-Kopeć et al., 2020; Silva et al., 2020). Alteration in the SCFAs production levels due to disruption in gut microbiota, i.e. losing the bacterial taxa that produce such molecules, were correlated to several human diseases such as autism (Liu et al., 2019), multiple sclerosis (Melbye et al., 2019) and Inflammatory Bowel Diseases (IBD).

Throughout the host life the diversity of microbiota is affected by several factors including, environmental factors, host genetics, antibiotics, nutrition and health state either during wellness or diseases (Laursen et al., 2021; Senn et al., 2020). Among the all factors, antibiotics possess the inhibitory affect on the distribution of gut microbiota, several studies demonstrated the potent impact of medications on gut microbiota (Ramirez et al., 2020; Konstantinidis et al., 2020). However, the impact of long-term use of medicines on the diversity of gut microbiota is rarely studied. Therefore, the aim of this study is to investigate the impact of drugs on the gut bacterial population.

2 Materials and methods

3 Results

The influence of three commonly prescribed long-term medications for chronic diseases, Amlodipine, Metformin, and Atorlip (atorvastatin calcium) were screened for their antimicrobial activity against several human gut probiotics and potential pathogens. The chemical structure of the medicines was illustrated in Fig. 1.

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Fig. 1

Chemical structure of amlodipine, metformin and atorlip.

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The findings of susceptibility to these medications revealed that metformin and atorlip showed no antibacterial activity at 10 mg concentration against the selected bacteria. Moreover, significant results were reported with amlodipine which possesses potent antibacterial activity against all the tested bacteria as indicated in Fig. 2, the gut probiotic B.casei and E. coli ATCC 25,922 both significantly influenced by this drug with a zone of inhibition of 30 mm and 24 mm, respectively (Fig. 3). The activity of amlodipine against remaining strains including L. plantarum KACC 15357, Acinetobacter sp.ATCC 49139, K. pneumonia ATCC 13,883 and S. typhimurium ATCC 14,028 was moderate range between 16 and 20 mm zone of inhibition. In contrast, P. aeruginosaATCC 27,584 was less susceptible by amlodipine with and the zone of inhibition was 12 mm. In comparison to the control antibiotic, the effect of pressure medication towards bacterial strains including B. casei, Acinetobacter sp., L. plantarum was higher in contrast to other microbes which were more susceptible to streptomycin than amlodipine (Fig. 2) (p > 0.05).

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Fig. 2

Antimicrobial activity of amlodipine, metformin and atorlip on probiotic and pathogenic bacterial strains.

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Fig. 3

The impact of three medications against B. casei and E. coli. C; standard antibiotic control (streptomycin, 10 µg), 1: amlodipine (10 mg), 2: metformin (10 mg) and 3: atorlip (10 mg).

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To determine the minimum inhibitory concentration (MIC) of amlodipine, micro-broth plate (96 well) method was used at various concentrations; 5, 2.5, 1.25, 0.625, 0.312, 0.156, 0.078 and 0.039 mg. The findings of the MIC test showed high consistency with the agar-well diffusion assay. The MIC values for B. casei and Acinetobacter sp. were the lowest by 0.078 and 0.039 mg, however, approximately the half of tested bacteria showed MIC value of 0.156 mg including L. plantarum, E. coli and S. typhimurium while the growth of K. pneumonia mostly inhibited at a concentration of 0.312 mg. Similarly, among all bacterial strains as in well diffusion results, P. aeruginosa showed the lowest susceptibility to pressure medications and the MIC value was 0.612 mg.

4 Discussion

The human body contains>100 trillion symbiotic microbes, which have a significant impact on human health (Young, 2017; Wang et al., 2017). Recently research reported that gut microbiota interaction with several medications by which the microbiome may interfere with the pharmacologic treatments leading to impact the drug's efficacy (Zhang et al., 2020; Walsh et al., 2018), in contrast, these medications may show antimicrobial properties against gut microbiota leading to imbalance or disruption the gut microbiota structure (Vich Vila et al., 2020), a growing number of studies have demonstrated that intestinal dysfunctions and pathological states may be caused by dysbiosis in the gut microbiota (Zha et al., 2020). Several studies reported that antibiotics play a significant role in the imbalance the gut microbiome composition leading to rise the antibiotic resistance (Francino, 2016; Langdon et al., 2016; Ramire et al., 2020), however, other studies attributed the prevalence of antimicrobial resistance to components other than antibiotics, such components including non-antibiotic molecules, metals and biocides have antimicrobial activity. Among them, it is believed that prescribed medicines significantly affect the composition of the gut microbiota (Ko et al., 2017). Statins are well-known medications used as first-line therapy for lowering cholesterol (Berne et al., 2005). Statin drugs found to have negative impact on gut microbiota structure in multiple microbiome studies (Dias et al., 2020; Vieira-Silva et al., 2020). Kim et al. (2019) have demonstrated that statin consumption is implicated in increasing the abundance of bacterial genera including Bacteroides, Butyricimonas, and Mucispirillum that are associated with intestinal inflammation in mice due to the release of inflammatory factors such as Interleukin 1 beta (IL-1β) and Transforming growth factor β (TGFβ1). Although, the present finding did not show any antibacterial properties for cholesterol-lowering drug atorlip tablets (Atorvastatin calcium) at the concentration of 10 mg/L against tested the tested bacteria. In a study conducted by Ko et al. (2017) found that MIC for list of statins drugs are atorvastatin, fluvastatin, lovastatin, pravastatin, pitavastatin, rosuvastatin and simvastatin, which exhibited an antibacterial properties against both gut and pathogenic bacteria at concentrations between 32 and > 1,024 µg/mL. Despite that metformin showed no activity towards any of bacterial strains included in this study at concentration of 10 mg/well, nevertheless, microbiome studies showed that such medicine possess a negative impact on gut microbiota. Studies investigated the effect of metformin on diversity of gut microbes in patients with obesity and type 2 diabetes mellitus showed a significant alteration in gut microbiota composition, members of Bacteroidetes and Verrucomicrobiaphyla were significantly shifted while the most affected genera were Escherichia, Akkermansia and Bacteroides (Zhang and Hu, 2020; Silamiķele et al., 2021). Chen et al. (2022) reported that administration of metformin resulted in elevating the abundance of gut probiotic SCFAs-producer Akkermansiamuciniphila which have a positive impact on the host body health. Amlodipine is a drug that lowers blood pressure and treats coronary artery disease (Cussotto et al., 2019), the interaction studies between gut microbiota and amlodipine mostly focused on the influence of microbiota on metabolized of amlodipine . Yoo et al. (2016) showed that the systemic amlodipine bioavailability was elevated when this drug was administered alongside antibiotics, co-administered, which indicates the involvement of gut microbiota in the biotransformation of amlodipine leading to a decrease its bioavailability and eventually resulted in resistance to amlodipine. Conversely, the effect of this medication on the diversity of gut microbes was not investigated yet according to our knowledge,the in vitro findings of this study on the impact of amlodipine on the list of gut bacterial strains predicted that such medication potentially possess significant effect on composition of gut microbiota.

5 Conclusion

In conclusion, non-antibiotic therapies proved to remarkable induce a notable shift in gut microbiome diversity as demonstrated in many studies. The present findings revealed that two of the used medicines (metformin and atorlip) showed no antimicrobial properties, in contrast, amlodipine reflected a potent impact against all examined microbes either probiotics or potential pathogens at very low concentrations. Further works are required to study the impact of these drugs on probiotic or pathogenic strains.