The human gut is a complex flora microecological environment that contains more than 80% of the microorganisms that live in the human body. The intestinal flora can be divided into beneficial and harmful flora according to their impact on the health of the host. Microecology believes that when the beneficial flora inhabiting the human intestine is numerically dominant, it is beneficial for the body to maintain health. Usually, the composition of intestinal flora in healthy people is relatively stable, but it varies with season, age, diet, disease, medication and individual differences. Under the influence of certain factors, the pathological state caused by the disruption of the balance between the normal microbiota of the organism and the microorganisms that make up the normal microbiota is called microbial imbalance, including dysbiosis and bacterial translocation. The former refers to the decline in the number of intestinal flora of origin and the proliferation of potentially pathogenic bacteria, while the latter refers to the passage of intestinal flora through the intestinal mucosa to localized mesenteric lymph nodes or more distant tissues due to altered intestinal permeability. The factors causing microbial imbalance include both host and microecological environment factors. Host factors include maladaptation of the organism to the environment, illness and adverse reactions to therapeutic measures (such as intestinal resection, gastrectomy and other surgical procedures, immunosuppressants, antibiotics, radionuclide application); microecological environment factors include invasion of foreign invading bacteria and the influence of antimicrobial drugs. Therefore, the pathogenicity is determined by the conversion process of intestinal microecological balance and dysbiosis. The treatment of intestinal dysbiosis with probiotic preparations overcomes the treatment orientation of antibiotics as purely bactericidal or antibacterial, but promotes the normal flora to give full play to the biological antagonism to get rid of the pathogenic bacteria, which is called “helping the righteous to get rid of the evil”, thus avoiding the practical problems such as the increase of drug-resistant strains and the spread of drug-resistant factors caused by the abuse of antibiotics. At present, it is widely used in the clinical application of intestinal diseases. The more widely used ones are Pepcid, which contains Bifidobacterium, Enterococcus and Lactobacillus, Bifidobacterium, which is mainly Bifidobacterium, Meichangan, which contains Bacillus subtilis, Enterococcus, and Lactase, Typhimurium, etc.
1.The application of probiotics in digestive system diseases
Probiotics (probiotics) has the role of adjusting the intestinal flora dysbiosis and improving the microbial environment, so it has good preventive and therapeutic effects on various causes of acute and chronic diarrhea and constipation and other digestive system diseases.
1.1 Diarrhea
Probiotics can improve the symptoms of diarrhea patients by regulating the balance of intestinal flora, restoring intestinal regulation and increasing colonization resistance and other mechanisms. A multicenter, randomized, double-blind, parallel-controlled clinical study showed that subjects showed significant improvement in diarrhea symptoms without significant adverse effects. This study showed that both Meclizine and Pepcid were effective in the treatment of acute and chronic diarrhea, both of which promote intestinal microbial balance and exert beneficial effects in humans. The treatment of fungal enteritis also showed that the use of probiotic preparations for fungal enteritis has the same efficacy as the use of antifungal ketoconazole, and no adverse reactions of antifungal drugs occurred, which is worthy of clinical promotion.
1.2 Constipation
Probiotics produce organic acid during the reproduction process, which makes the intestinal lumen PH drop and regulates the normal peristalsis of the intestine, and at the same time makes the osmotic pressure of the intestinal tube increase and the secretion of water increase, softening the stool, thus relieving constipation. The test results for both adults and children show that probiotic preparations have good efficacy in the adjuvant treatment of functional constipation in adults and functional constipation in children.
1.3 Helicobacter pylori (HP) infection
In vitro tests confirmed that Lactobacillus salivarius could inhibit the adhesion of HP and the secretion of IL-8 in vitro, and HP could not colonize the gastric mucosal surface in the stomach of rats pre-inoculated with Lactobacillus salivarius. At the same time, probiotic preparations can also reduce or block the adverse effects of gold standard drugs for the treatment of HP, for example, the combination of Lactobacillus can significantly reduce the adverse effects such as diarrhea, nausea and taste disorder produced by triple therapy anti-HP treatment.
1.4 Inflammatory bowel disease
Inflammatory bowel disease (IBD) is a chronic inflammatory disease that occurs mostly in the colon and rectum, and is prone to recurrence and fluctuating severity. IBD mainly includes Ulcerative colitis (UC) and Crohns disease (CD), which are clinically distinguished by the intestinal localization of the inflammation, local features, familial concentration and complications. This inflammatory response is most often the result of altered intestinal permeability and is most typical of the ileal segment.
Molecular biology analysis shows that the communal relationship between intestinal microorganisms and their hosts is necessary for host growth and development, and is the result of a mutually beneficial symbiosis and long-term co-evolution. Both animal models and human trials have shown that this symbiotic relationship is commonly dysfunctional in IBD. Therefore, intestinal microecology is an ideal therapeutic target with minimal adverse effects. However, the results of clinical trials reported in the literature on the application of probiotics for IBD are controversial, but the simultaneous or late application of probiotics along with known effective therapeutic agents is undoubtedly beneficial in restoring intestinal flora and function.
1.5 Irritable bowel syndrome (IBS)
Double-blind, randomized, controlled clinical trials on probiotic treatment of IBS have been reported both at home and abroad, all of which have confirmed good clinical efficacy and can effectively alleviate various symptoms of IBS, and all of which have a low incidence of adverse effects. However, more extensive multicenter clinical studies are lacking.
1.6 Application in the prevention and treatment of liver disease
Patients with liver disease commonly have intestinal dysbiosis with varying degrees of enterogenic endotoxemia, and the severity of dysbiosis is generally proportional to the degree of liver function impairment. Probiotics can restore the normal intestinal flora, maintain the integrity of the intestinal mucosal barrier, absorb and utilize nitrogenous and harmful substances in the intestinal tract, thus reducing the source of intestinal endotoxin and bacterial translocation, inhibiting the growth of ammonia-producing spoilage bacteria, reducing the acidity, blood ammonia level and plasma endotoxin level in the intestinal tract of patients with cirrhosis, and thus can play a good role in the treatment of acute and chronic hepatitis, spontaneous bacterial peritonitis and other complications. The therapeutic effect.
1.7 Severe acute pancreatitis
Severe acute pancreatitis (SAP) has an acute onset, complex condition, involves many organs, has a high incidence of complications, and is prone to intestinal dysmotility, intestinal flora dysbiosis, and rectal dysfunction. Therefore, maintaining the integrity of the intestinal barrier plays an important role in the treatment of severe acute pancreatitis, which can effectively prevent bacterial translocation and reduce the incidence of systemic inflammatory response syndrome and secondary multi-organ system dysfunction. Experimentally, it has been proved that the addition of probiotics during early enteral nutrition in SAP can reduce complications and alleviate the disease and shorten the number of hospital days.
2.Anti-cancer and anti-tumor effect of probiotics
The anti-tumor effect of probiotics is mainly reflected in the metabolites generated to optimize the combination of intestinal flora, enhance the immune function of the body, while anti-cancer probiotics can degrade nitrosamines to eliminate their carcinogenicity, in addition, probiotics can also promote intestinal peristalsis, so that harmful bacteria excluded from the body. These beneficial effects are particularly prominent in the prevention and treatment of colon and liver cancer, and the possible mechanism is to play a very important role in the degradation of carcinogens such as aflatoxins.
3.Probiotics regulation of vaginal diseases
Lactobacillus is the most important and abundant resident bacteria in the normal vaginal flora, accounting for more than 95% of the resident bacteria in the vagina. It produces lactic acid by enzymatic digestion of glycogen in the epithelial cells of the vaginal mucosa to maintain an acidic environment in the vagina, inhibits the overgrowth of harmful bacteria and facilitates the self-cleaning effect of the vagina, and is the main bacterium that maintains the balance of the vaginal flora. However, ageing, extensive use of antibiotics, surgery, childbirth, improper vaginal irrigation, sexual diseases, hormonal changes during the menstrual cycle, sexual intercourse, and poor hygiene habits can disrupt the micro-ecological balance of the vagina, leading to vaginal dysbiosis and vaginal diseases, such as bacterial vaginosis and trichomoniasis. Bacterial vaginosis is mainly manifested by dysbiosis in which lactobacilli in the vagina are significantly reduced or completely disappeared, while trichomoniasis is a sexually transmitted disease with a higher incidence, mainly manifested by increased isolation of Trichomonas, Mycoplasma, Streptococcus and anaerobic flora from vaginal secretions, with insignificant changes in other microorganisms. Studies have shown that the local application of H2O2-producing Lactobacillus in probiotics can all achieve high efficiency.
4, clinical application of probiotic preparations precautions
Clinical application of probiotic preparations should pay attention to the following points.
4.1 Rational application of antibiotics, whether the simultaneous use of antibiotics and microecological preparations affect the efficacy of live bacteria preparations is a noteworthy issue. Experiments have shown that rectified intestine can not be used simultaneously with 28 antibiotics such as ciprofloxacin, ofloxacin, gentamicin, tobramycin, doxycycline, cefazolin sodium, cefradine, cefalexin, amoxicillin/clavulanic acid potassium, furazolidone, metronidazole, etc. because of their sensitivity, but it can be used simultaneously with erythromycin, azithromycin, clindamycin, etc. because of their resistance. And Peficon should not be taken at the same time with vancomycin, ciprofloxacin, compound piperacillin, tetracycline, compound sulfamethoxazole, ampicillin, metronidazole, etc.
4.2 Rational selection of microecological agents according to different diseases: Some scholars have studied that the efficacy of pefikon in treating infant diarrhea is better than the combined application of various microecological agents such as rectified intestine, therefore, the combined application of various microecological agents should not be used blindly.
4.3 Storage conditions and storage: The number of live bacteria and survival time of microecological preparations are closely related to the storage conditions. Live bacteria are generally afraid of light, heat and humidity, etc. The higher the temperature and humidity, the shorter the survival time of live bacteria. Some preparations, such as Pepcid, Jin Shuangqi and Changlekang, are marked to be stored in cold places, and some preparations have no special requirements and are valid for up to 24 months, which brings great convenience to both sales and patients, and helps to improve patient compliance and treatment effect.
4.4 Pay attention to the method of administration: Pefikang, Lizhu Enteral and other preparations can not tolerate heat and stomach acid, need to be taken after meals, should not use hot water and should be served with warm water.
5.The safety of probiotics
Probiotic preparations are a class of preparations that have less effect on liver and kidney function and are safer, mainly allergic reactions should be observed, but there are reports of adverse reactions such as bacteremia, sepsis and cholangitis in some patients, it should be pointed out that there is no direct evidence to confirm that probiotics must have caused these infections, because the reported people are suffering from underlying diseases, for immune deficiencies, poor resistance It is important to use caution in the elderly with immune deficiencies and poor resistance.
As a new industry, probiotic preparations have broad prospects in clinical practice and deserve wide attention. As long as we develop them scientifically and use them rationally, they may bring unexpected and extraordinary clinical effects.