CN109700837B - Anti-hyperuricemia plateau nettle extract, preparation method and application thereof - Google Patents

Abstract

The invention provides a plateau nettle extract for resisting hyperuricemia and a preparation method thereof. The plateau nettle extract for resisting hyperuricemia is the Tibetan medicine plateau nettle alcohol-soluble part, has the effects of resisting hyperuricemia, inhibiting liver XOD activity and regulating kidney uric acid transporter gene expression, and can be used for preparing a medicine for resisting hyperuricemia.

Description

Anti-hyperuricemia plateau nettle extract, preparation method and application thereof

Technical Field

The invention relates to the technical field of medicines, in particular to an effective part with an anti-hyperuricemia effect extracted from Tibetan medicine plateau urtica and a preparation method thereof.

Background

Uric acid (Uric acid) in vivo is the final product of hypoxanthine and xanthine under the catalysis of xanthine oxidase. Namely, the metabolic disorder of purine substances causes the increase of uric acid production, which leads to the increase of uric acid concentration in vivo and Hyperuricemia (Hyperuricemia). Hyperuricemia is the biochemical basis for the development of Gout (Gout). Gout is accompanied by hyperuricemia. With the continuous improvement of living standard and the change of dietary structure, the prevalence rate of gout and hyperuricemia is on the rising trend year by year. At present, the drugs clinically used for treating gout and hyperuricemia mainly comprise colchicine, non-steroidal anti-inflammatory drugs, glucocorticoid and the like, and are used for treating a plurality of side effects and limiting the application. The present invention selects potassium oxonate as a chemical inducer to cause mice to generate polar hyperuricemia and also can damage renal function to cause blood creatinine to rise. The method is simple and has good reproducibility. The pathogenesis of gout and hyperuricemia is currently considered to be related to purine metabolic disorder and/or uric acid excretion disorder. The application discusses the effect of reducing uric acid at different extraction parts of high-grade nettle by detecting the activities of serum UA, CRE and BUN, liver XOD, serum ADA and kidney uric acid transporter gene expression as indexes.

The dry aerial parts of the Urticaceae plant Tibetan medicine plateau Urtica hyperborea Jacq. exWedd, is one of the basic sources of the characteristic Tibetan medicine, Suzhu wood (Suzhu). The traditional works of Tibetan medicine in many parts are well documented, for example, in the four medical classics and the Jingzhu Bencao, the overground part, inflorescence, infructescence and seeds of the traditional Chinese medicine are all used as medicines, have the effects of dispelling wind and arresting convulsion, warming stomach and promoting digestion, and are used for treating chronic heat (old heat), stomach cold, dyspepsia, diabetes, rheumatic pain, hypertension, postpartum convulsion, infantile convulsion, urticaria and the like caused by the dragon disease. Plateau nettle is a folk Tibetan medicine commonly used for treating digestive system diseases and arthralgia. Modern pharmacological research reports that the plant has wide pharmacological activities of resisting inflammation, easing pain, resisting rheumatism and rheumatoid diseases, resisting prostatic hyperplasia, resisting bacteria, resisting oxidation, reducing blood sugar, regulating blood fat and the like. So far, no report about the effect of the high-grade nettle on the hyperuricemia is found.

Disclosure of Invention

In view of the above problems, the present invention aims to provide a drug effective extraction site, which has the effects of reducing uric acid, inhibiting liver XOD and regulating renal uric acid transporter gene expression, and can be used for preparing drugs for treating hyperuricemia and resisting gout.

In order to confirm the uric acid reducing effect of the extracted part, the treatment effect of the plateau nettle petroleum ether extracted part, the ethyl acetate extracted part, the n-butanol extracted part and the alcohol-soluble part on hyperuricemia model mice induced by oxonate is respectively examined by taking allopurinol as a positive control. The experimental result in the body of the mouse shows that the plateau alcohol-soluble part of the nettle has better uric acid reducing treatment effect on hyperuricemia model mice induced by potassium oxonate.

A preparation method of a plateau nettle extract for resisting hyperuricemia comprises the steps of preparing a normal butanol extract and preparing an alcohol-soluble part, and comprises the following steps:

1) extracting plateau nettle with ethanol and water respectively to obtain ethanol extract part and water extract part;

2) sequentially extracting the ethanol extraction part with petroleum ether and ethyl acetate, and removing the part with small polarity to obtain an elution mother liquor;

3) extracting the elution mother liquor with n-butanol, collecting n-butanol extract, concentrating under reduced pressure, and drying to obtain n-butanol extract;

4) concentrating the water extract part in the step 1) under reduced pressure, precipitating with 4-6 times of 95% ethanol, pouring out supernatant, washing precipitate with 95% ethanol, mixing supernatants, and concentrating until there is no ethanol smell to obtain ethanol soluble part.

The operation of respectively extracting plateau nettle by using ethanol and water in the step 1) comprises the following steps:

1) drying coarse powder of plateau nettle;

2) wetting with 95% ethanol, placing in a percolation barrel, soaking with 95% ethanol overnight, and percolating with 8-10 times of 95% ethanol and 50% ethanol; collecting percolate by stages, mixing the percolates, recovering under reduced pressure until no alcohol smell exists, and dissolving in water to obtain ethanol extract;

3) percolating the residue with water ladder 8-10 times the weight of the medicinal materials, collecting percolate, and recovering under reduced pressure to obtain water extract.

The plateau nettle extract is a large-polarity part of the plateau nettle; the big polar part is one or the mixture of two of the normal butanol extract or the alcohol soluble part extract of the plateau nettle obtained by the method in claim 1.

The plateau nettle extract for resisting hyperuricemia is an alcohol-soluble part extract.

The plateau nettle extract for resisting hyperuricemia is a n-butyl alcohol extract.

The use of the high altitude nettle extract in the preparation of a medicament for treating hyperuricemia.

Compared with the prior art, the invention has the following advantages:

1. the Tibetan medicine plateau nettle is a dry overground part of a Urticaceae plant plateau Urtica hyperborea Jacq.ex Wedd, is a special medicinal material commonly used for preventing and treating digestive system diseases, arthralgia and the like in Tibetan areas, has a good medication basis, and is characterized by being applied to the overground part. Through tests, the medicine has the effect of reducing uric acid.

2. The effective extraction part of the medicine of the invention has no toxic and side effect.

3. The medicine of the invention is high in effective extraction part of the original nettle, simple in preparation process and high in extraction rate, and provides a good foundation for industrial production of the medicine.

4. The Tibetan medicine plateau nettle is beneficial to development and utilization of national medicine resources.

The effect of extracting parts of high altitude nettle is demonstrated by the following specific examples.

Drawings

FIG. 1 shows fingerprint of n-butanol fraction extract of plateau nettle;

FIG. 2 shows fingerprint of alcohol-soluble extract of high altitude nettle;

FIG. 3 is a comparison graph of fingerprint spectra of n-butanol fraction of plateau Urtica dioica and various drugs of Urtica;

FIG. 4 is a comparison graph of fingerprint spectra of high altitude Urtica alcohol extract and various medicinal materials of Urtica;

FIG. 5 is a graph of the effect of plateau Urtica dioica extract on the serum UA level in mice with hyperuricemia; in the figure, compared with the Normal group,^*P<0.05,^***P<0.001; in comparison with the Hyperuricemia group,^#P<0.05,^##P<0.01；

FIG. 6 is a graph of the effect of elevated plain nettle extract on serum CRE levels in mice with hyperuricemia; in the figure, compared with the Normal group,^*P<0.05,^***P<0.001; in comparison with the Hyperuricemia group,^#P<0.05,^##P<0.01；

FIG. 7 is a graph showing the effect of elevated plain nettle extract on the serum BUN level in mice with hyperuricemia; in the figure, compared with the Normal group,^*P<0.05,^***P<0.001; in comparison with the Hyperuricemia group,^#P<0.05,^##P<0.01；

FIG. 8 shows the activity of plateau Urtica dioica extract on the liver XOD of hyperuricemia mice; in the figure, in comparison with Normal: p<0.05; in comparison with Hyperuricemia,^#P<0.05,^##P<0.01；

FIG. 9 shows the activity of plateau Urtica dioica extract on the liver XOD of hyperuricemia mice; in the figure, in comparison with Normal:^*P<0.05; in comparison with Hyperuricemia,^#P<0.05,^##P<0.01；

FIG. 10 shows the activity of plateau Urtica dioica extract on serum ADA of mice with hyperuricemia; comparison with Normal:^*P<0.05; in comparison with Hyperuricemia,^#P<0.05,^##P<0.01；

FIG. 11 is a graph of the effect of high altitude nettle extract on the expression of kidney OAT1mRNA in mice with hyperuricemia; in the figure, compared to the Normal group:^**P<0.01; comparison with the Hyperuricemia group:^##P<0.01；

FIG. 12 is a graph of the effect of high altitude nettle extract on the expression of URAT1mRNA in the kidney of mice with hyperuricemia; in the figure, P is compared with Normal group<0.01; comparison with the Hyperuricemia group:^##P<0.01；

wherein, in fig. 3, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13 and n-butanol fraction extracts of Sinkiang Urtica;

in fig. 3, 1. wide-leaved nettle 2. special nettle 3. split-leaved nettle 4. narrow-leaved nettle 5. triangle-leaved nettle 6. plateau nettle 7. Tibetan nettle 8. nettle 9. Xinjiang special nettle 10. Himalayan nettle 11. Yunnan nettle 13. alcohol-soluble fraction extract of high-leaved nettle.

Detailed Description

Example 1 comparative analysis of the composition of high-altitude nettle, the composition of the high-altitude nettle's large polar region and other species of the Urtica genus

Wetting dry coarse powder of high altitude nettle with 95% ethanol at room temperature, pouring into a percolation barrel, adding 95% ethanol until the liquid level is higher than the surface of the medicinal material, soaking overnight, performing gradient percolation with 8-10 times of the weight of the medicinal material of 95% ethanol, 50% ethanol and water in sequence, collecting percolate by stages, and concentrating under reduced pressure until no alcohol smell exists to obtain 95% ethanol extract, 50% ethanol extract and water extract; dispersing 95% ethanol extract and 50% ethanol extract with appropriate amount of water, sequentially extracting 95% ethanol extract and 50% ethanol extract with equal amount of petroleum ether, ethyl acetate and n-butanol for 5-7 times (until organic phase is colorless), mixing the same organic phases, and recovering organic solvent under reduced pressure to obtain petroleum ether phase, ethyl acetate phase and n-butanol phase extract, wherein the n-butanol phase extract is high altitude nettle n-butanol extract; recovering water extract under reduced pressure, concentrating to appropriate amount, precipitating with 95% ethanol for 2 times (the amount of ethanol is 4-6 times of the volume of the medicinal liquid), decanting the supernatant, washing the precipitate with 95% ethanol, mixing the supernatants, concentrating until there is no ethanol smell, and concentrating to obtain ethanol soluble extract.

Respectively collecting 11 medicinal materials of Urtica, precisely weighing 1g of dried medicinal material powder of 11 medicinal plants of Urtica, placing in 100mL round bottom flask, adding 25mL of methanol, shaking, ultrasonic extracting in 70 deg.C water bath for 30min, standing, cooling, centrifuging the supernatant, and filtering with 0.45 μm microporous membrane.

The instrument is as follows: shimadzu LC-20A ultra high performance liquid chromatograph equipped with PDA ultraviolet detector (Shimadzu corporation, Japan); KQ-5200DB ultrasonic cleaning machine (Kunshan ultrasonic Instrument Co.); model AL204 electronic analytical balance [ Mettler Toledo instruments (shanghai) ltd ]; electronic balance (one hundred thousand, sartorius model BT 124S); an ORTEX3 vortex mixer (IKA, germany); BUCHI electric rotary evaporator (cheque switzerland); millipore-silicon ultrapure water treatment system (Merck Millipore, Germany). The reagent is as follows: acetonitrile (chromatographic grade, Tedia corporation, usa); formic acid [ chromatographic grade, Aladdin reagent (Shanghai) Co., Ltd ]. The water is ultrapure water, and other reagents are analytically pure. The chromatographic methods are shown in table 1.

TABLE 1 conditions of mobile phase of Urtica herbs

The specific components of the alcohol-soluble part extract or the n-butanol part extract of the plateau urtica are proved to have obvious difference with the components of the wide-leaf urtica, the special-plant urtica, the split-leaf urtica, the narrow-leaf urtica, the triangle-leaf urtica, the Tibetan urtica, the nettle, the Xinjiang special-plant urtica, the himalayan urtica and the Yunnan urtica through the qualitative identification of the chromatogram. As shown in particular in fig. 1, 2, 3 and 4.

Example 2 Activity Studies of extracts of the polar parts of high altitude nettle

Respectively collecting 11 medicinal materials of Urtica, precisely weighing 1g of dried medicinal material powder of 11 medicinal plants of Urtica, placing in 100mL round bottom flask, adding 25mL of methanol, shaking, ultrasonic extracting in 70 deg.C water bath for 30min, standing, cooling, centrifuging the supernatant, and filtering with 0.45 μm microporous membrane.

The preparation method of the extract of the large polar part of plateau nettle is described in example 1.

1. Materials and methods

Allopurinol (purity ≥ 98%, HPLC assay) Sigma, st.louis, MO; potassium Oxonate (purity ≥ 98%, HPLC assay) from Sigma, St.Louis, MO); uric acid assay kit (microplate method) (lot No. 20171114); urea dipstick kit (batch No. 20180929); blood creatinine assay kit (batch No. 20181012); adenosine deaminase detection kit (batch No. 20181008); XOD determination kit (batch No. 2017103) and Coomassie brilliant blue protein test kit (batch No. 20171107) were purchased from Nanjing institute of bioengineering. Trizol reagent (Ambion, lot # 152105), reverse transcription kit (Novoprotein, lot # 0511171); enzyme-free water (Solarbio, batch: R1600); primers for OAT1, URAT1, and GLUT9 were synthesized by biotechnology limited of beijing dingshi. Other reagents were analytically pure.

1.1 instruments

A knife type coarse particle pulverizer (Shanghai Chinese medicine machinery plant, model: FD200T) ultra-low temperature refrigerator (ThermoFisher corporation, USA, model: 808964-1601); a desktop high speed refrigerated centrifuge (Eppendorf corporation, USA, model 5430); a full-wavelength microplate reader (ThermoFisher corporation, USA, model 1510-01871); PCR apparatus (Bio-Rad, model: 7500); DY89-II electric homogenizer (Ningbo Xinzhi Biotechnology GmbH, model: T10S).

1.2 Experimental animals

Mice, KM species, weight 25-28 g (provided by Experimental animals center of Jiangxi Chinese medicinal university), certification number: SCXK (gan) 2018 and 0003. The animal experiment is approved by the ethical committee of experimental animals of the university of traditional Chinese medicine in Jiangxi and conforms to the guidance principle of the ethical committee of China.

2 method of experiment

After 1 week of adaptive feeding of 110 mice, they were randomly grouped into 10 mice per cage, and divided into a blank group (Normal group), a Hyperuricemia model group (Hyperuricemia group), an Allopurinol group (Allopurinol group), a Low Petroleum ether extraction site Low dose group (Low Petroleum ether extract group, LPG), a High Petroleum ether extraction site High dose group (High Petroleum ether extract group, HPG), a Low Ethyl acetate extraction site Low dose group (Low Ethyl acetate extract group, LEG), a High Ethyl acetate extraction site High dose group (High Ethyl acetate extract group, HEP), a Low N-butanol extraction site Low dose group (Low N-butanol extract group, LBG), a High N-butanol extract site group (High N-butanol extract group, Low alcohol extract group (LAG), a High alcohol soluble site group (Low alcohol extract group, LAG), HAG), 11 groups in total (table 2). The blank group and the model group are given with normal saline with corresponding volume, the positive drug group is given with allopurinol, the allopurinol is suspended in 0.5 percent sodium carboxymethylcellulose (CMC-Na) solution, and the gastric perfusion amount is 10ml kg^-1. The administration was continued for 7d, and the gavage was administered 1 time per day. Injecting Potassium Oxonate (suspended in 0.5% CMC-Na solution) into abdominal cavity of mouse 1 hr before the last administration at a dose of 350 mg/kg^-1To create a mouse acute hyperuricemia model, the blank group was intraperitoneally injected with 0.5% CMC-Na in the same dose.

TABLE 2 grouping of mice experiments and dosing

Grouping	Dosage (g.Kg) of crude drug for mice-1)	Dosage (mg. Kg)-1)
			Blank group	-	-
Model set	-	-
			Allopurinol (positive drug) group	-	10
Low dose group of petroleum ether extraction sites	0.78	11.7
			High dose group of petroleum ether extraction sites	2.34	35.1
Low dose group of ethyl acetate extract fraction	0.78	2.57
			Ethyl acetate extract fraction high dose group	2.34	7.72
N-butanol extraction fraction low dose group	0.78	4.29
			High dosage group of n-butanol extraction fraction	2.34	12.87
Alcohol soluble part low dose group	0.78	78
			Alcohol soluble fraction high dose group	2.34	234

3 taking materials

1h after administration, blood is collected from orbit, and whole blood is 5000 r.min^-1Centrifuging for 10min, collecting supernatant, and storing in refrigerator at 4 deg.C. And (3) taking a part of the largest leaf of the liver on an ice bench, freezing and storing the kidney at minus 80 ℃, and detecting.

4 detection of serum Uric Acid (UA), Creatinine (CRE), Urea Nitrogen (BUN) levels

The detection steps and methods are performed strictly according to the instructions.

5 determination of liver XOD and serum Adenosine Deaminase (ADA) Activity

(1) Determination of liver XOD activity: taking liver tissue block 0.1g, adding 9 times volume of 0.9% ice physiological saline, mechanically homogenizing to obtain homogenate with concentration of 10%, and centrifuging at fast-freezing high speed centrifuge for 5000r min^-1Centrifuging for 10min, collecting partial supernatant, and diluting with 0.9% ice physiological saline at a ratio of 1:9 to obtain 1% tissue homogenate. The XOD activity in 10% homogenate of liver and the tissue protein content in 1% homogenate of liver were measured respectively according to the method specified in the kitAnd calculating the relative activity of XOD in the liver tissue.

(2) Determination of serum ADA activity: the detection steps and methods are performed strictly according to the instructions.

6RT-PCR method for detecting expression of Urtica dioica extract on kidney URAT1mRNA and OAT1mRNA

Reference methods PCR amplification primers were designed with the sequences as in table 3. Freezing kidney tissue at-80 deg.C, weighing cortex tissue 50-100mg, extracting total RNA by TRIzol method, and identifying its purity and integrity. The total RNA was subjected to reverse transcription (20. mu.L reaction system) to obtain a cDNA template. RT-PCR reaction conditions: 90 ℃, 30s, annealing temperature 58 ℃, 35s, 35 cycles, extension for 10min at 72 ℃.

TABLE 3 primer information Table

Table 2Primer information

8 results of the experiment

(1) Influence of plateau Urtica dioica extract on levels of UA, CRE and BUN in serum of mouse with hyperuricemia

As can be seen from Table 4, compared with the blank group, the serum UA, CRE and BUN levels of the model group mice are all obviously increased (P <0.0001 and P <0.05), indicating that the modeling is successful. After 1 week of administration, compared with the model group, the allopurinol (positive drug) and plateau nettle extract all had the effect of reducing serum UA level, and simultaneously reducing serum CRE and BUN levels, especially the LAG and HAG dosage group is most significant (P < 0.01). The part can effectively reduce the serum UA level of a hyperuricemia model mouse and simultaneously plays a role in protecting the kidney function. In addition, the plateau nettle extract LBG and HBG can also effectively reduce the serum UA level (P <0.01) of a hyperuricemia mouse, is second to alcohol-soluble parts, and reduces the serum CRE and BUN content (P < 0.05). As shown in detail in fig. 5, 6 and 7.

TABLE 4 influence of elevated Urtica dioica on the serum UA, CRE, BUN levels in mice with hyperuricemia (x + -s, n ═ 10)

Table 3 Effects of U.hyperborean on the level ofUA、CRE、BUN ofserumin hyperuricemia mice(x±s,n＝10)

Note: compared with the Normal group, the test sample is,^*P<0.05,^***P<0.001; in comparison with the Hyperuricemia group,^#P<0.05,^##P<0.01；

Note:*Compared with the Normal group，^*P<0.05；^**P<0.001；

#Compared with the hyperuricemia group，^#P<0.05；^##P<0.01.

(2) influence of plateau Urtica dioica extract on liver XOD and serum ADA activity of mouse with hyperuricemia

As can be seen from Table 4, compared with the model group, the allopurinol group can obviously inhibit the activities of liver XOD and serum ADA of a hyperuricemia model mouse (P is less than 0.01), and the inhibition rate of XOD is 44.68%; the experimental group except the plateau nettle LBG group all inhibited the activity of liver XOD, the most significant of which was LAG group (P <0.01), the inhibition rate was 47.28%, which is better than allopurinol group, meanwhile, LAG and HAG of the part also inhibited the activity of serum ADA significantly (P <0.05, P < 0.01). The plateau urtica alcohol-soluble part is prompted to reduce the generation of xanthine and hypoxanthine in vivo by inhibiting the activity of liver XOD and ADA so as to reduce the generation of uric acid. As can be seen from table 4 and table 5, the effect of the plateau urtica extract dose groups on inhibiting the liver XOD activity of the mouse model with acute hyperuricemia is not parallel to the effect of the plateau urtica extract dose groups on the serum UA level, which indicates that other uric acid lowering mechanisms exist. As shown in fig. 8 and 9.

TABLE 54 influence of plateau Urtica dioica on XOD Activity of the liver of hyperuricemia mice (x + -s, n ═ 10)

Table 4 Effects of U.hyperborean onthe activity ofxanthine oxidase、serumADAofuric in hyperuricemia mice(x±s,n＝10)

Note: comparison with Normal:^*P<0.05; in comparison with Hyperuricemia,^#P<0.05,^##P<0.01；

Note:*Compared with theNormal group,*P<0.05，the hyperuricemia group，^#P<0.05,^##P<0.01；

(3) expression of plateau nettle extract on kidney OAT1 and URAT1mRNA of mouse with hyperuricemia

As can be seen from table 5, the model group significantly up-regulated the expression of mouse kidney URAT1mRNA, while significantly down-regulated the expression of OAT1mRNA, compared to the blank group. Compared with the model group, the allopurinol group, LPG, HPG, LEG and HAG group can obviously up-regulate the expression of the OAT1mRNA of the kidney of the hyperuricemia model mouse. The expression of the kidney URAT1mRNA of the mouse model of hyperuricemia is reduced by each extracted part of plateau urtica. In addition, the allopurinol (10mg/kg) group regulated the expression of URAT1 and OAT1 mRNA. As shown in fig. 10, 11 and 12.

Claims (5)

1. A preparation method of a plateau nettle extract for resisting hyperuricemia comprises the steps of preparing a normal butanol extract and preparing an alcohol-soluble part, and is characterized in that: the method comprises the following steps:

1) extracting plateau nettle with ethanol and water respectively to obtain ethanol extract part and water extract part;

2) sequentially extracting the ethanol extraction part with petroleum ether and ethyl acetate, and removing the part with small polarity to obtain an elution mother liquor;

3) extracting the elution mother liquor with n-butanol, collecting n-butanol extract, concentrating under reduced pressure, and drying to obtain n-butanol extract;

4) concentrating the water extract part in the step 1) under reduced pressure, precipitating with 95% ethanol with 4-6 times of the volume of the liquid medicine for 2 times, pouring out the supernatant, washing the precipitate with 95% ethanol, mixing the supernatants, and concentrating until no alcohol smell exists to obtain an alcohol-soluble part;

the operation of respectively extracting plateau nettle by using ethanol and water in the step 1) comprises the following steps:

1) drying coarse powder of plateau nettle;

2) wetting with 95% ethanol, placing in a percolation barrel, soaking with 95% ethanol overnight, and percolating with 8-10 times of 95% ethanol and 50% ethanol; collecting percolate by stages, mixing the percolates, recovering under reduced pressure until no alcohol smell exists, and dissolving in water to obtain ethanol extract;

3) percolating the residue with water ladder 8-10 times the weight of the medicinal materials, collecting percolate, and recovering under reduced pressure to obtain water extract.

2. An anti-hyperuricemia plateau nettle extract is characterized in that: the plateau nettle extract is a large-polarity part of the plateau nettle; the big polar part is one or the mixture of two of the normal butanol extract or the alcohol soluble part extract of the plateau nettle obtained by the method in claim 1.

3. The anti-hyperuricemia high altitude nettle extract according to claim 2, wherein: the anti-hyperuricemia plateau nettle extract is an alcohol-soluble part extract.

4. The anti-hyperuricemia high altitude nettle extract according to claim 2, wherein: the anti-hyperuricemia plateau nettle extract is a n-butyl alcohol extract.

5. Use of a high altitude nettle extract according to any one of claims 2, 3 and 4 in the manufacture of a medicament for use in the treatment of hyperuricemia.

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